WO2023137596A1 - Communication methods, terminal devices and network devices - Google Patents

Abstract

Provided are communication methods, terminal devices and network devices. A method comprises: if a first condition is satisfied, a terminal device starting a handover condition evaluation task related to conditional handover; and/or if a second condition is satisfied, the terminal device stopping or not starting the handover condition evaluation task related to conditional handover, wherein the handover condition evaluation task related to conditional handover is used for evaluating whether a conditional handover event associated with a first conditional handover target cell is fulfilled, the first conditional handover target cell is one of at least one conditional handover target cell corresponding to conditional handover configuration information configured by a network device, and the conditional handover configuration information configured by the network device comprises configuration information corresponding to the at least one conditional handover target cell. The present invention is beneficial to reducing the amount of power consumed by a terminal device for executing a handover condition evaluation task related to conditional handover, so as to improve the efficiency of the terminal device executing the handover condition evaluation task related to conditional handover.

Description

Communication method, terminal device and network device technical field

The present application relates to the technical field of communication, and more specifically, to a communication method, a terminal device, and a network device.

Background technique

The conditional handover mechanism can enhance the robustness of the terminal device handover process. Unlike traditional handover technologies, the conditional handover command can be sent to the terminal device very early. After receiving the conditional handover command, the terminal device will not immediately execute the handover command. Instead, it will first start the handover condition evaluation task related to the conditional handover to evaluate whether the conditional handover event associated with one or more conditional handover target cells is satisfied. If the conditional handover event is satisfied, the terminal device can switch to the conditional handover target cell associated with the conditional handover event, and after the conditional handover is successful, the terminal device will delete all saved conditional handover configuration information. At present, in order to reduce the overhead required for the network device to configure the conditional switching configuration information for the terminal device, the terminal device is configured not to delete all saved conditional switching configuration information after the conditional switching is successful. However, the conditional handover behavior of the terminal device after the conditional handover is successful is not specified in the existing communication protocol, which may lead to low efficiency of the terminal device in performing handover condition evaluation tasks related to the conditional handover.

Contents of the invention

The present application provides a communication method, a terminal device, and a network device, so as to improve the efficiency of the terminal device in performing handover condition evaluation tasks related to conditional handover.

In a first aspect, a communication method is provided, including: if a first condition is met, a terminal device starts a handover condition evaluation task related to conditional handover; and/or if a second condition is met, the terminal device does not start or stop a handover condition evaluation task related to conditional handover, wherein the handover condition evaluation task related to conditional handover is used to evaluate whether a conditional handover event associated with a first conditional handover target cell is satisfied, wherein the first conditional handover target cell is one of at least one conditional handover target cell corresponding to conditional handover configuration information configured by a network device, and the conditional handover configuration information configured by the network device includes the at least one conditional handover target cell Configuration information corresponding to the handover target cell.

In a second aspect, a communication method is provided, including: a network device sends a reconfiguration message to a terminal device, the reconfiguration message is used to instruct the terminal device to start a handover condition evaluation task related to conditional handover, and/or, the reconfiguration message is used to instruct the terminal device not to start or stop the handover condition evaluation task related to conditional handover, wherein the handover condition evaluation task related to conditional handover is used to evaluate whether a conditional handover event associated with a first conditional handover target cell is satisfied, wherein the first conditional handover target cell is one of at least one conditional handover target cell corresponding to conditional handover configuration information configured by the network device, the network The conditional handover configuration information configured by the device includes configuration information corresponding to the at least one conditional handover target cell.

In a third aspect, a terminal device is provided, including: if the first condition is met, a processing unit is configured to start a handover condition evaluation task related to conditional handover; and/or, if a second condition is met, the processing unit is configured to not start or stop the handover condition evaluation task related to conditional handover, wherein the handover condition evaluation task related to conditional handover is used to evaluate whether a conditional handover event associated with a first conditional handover target cell is satisfied, wherein the first conditional handover target cell is one of at least one conditional handover target cell corresponding to conditional handover configuration information configured by a network device, and the conditional handover configuration information configured by the network device includes at least Configuration information corresponding to a conditional handover target cell.

In a fourth aspect, a network device is provided, including: a sending unit configured to send a reconfiguration message to a terminal device, the reconfiguration message being used to instruct the terminal device to start a handover condition evaluation task related to conditional handover, and/or the reconfiguration message being used to instruct the terminal device not to start or stop the handover condition evaluation task related to conditional handover, wherein the handover condition evaluation task related to conditional handover is used to evaluate whether a conditional handover event associated with a first conditional handover target cell is satisfied, wherein the first conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information configured by the network device The conditional handover configuration information configured by the network device includes configuration information corresponding to the at least one conditional handover target cell.

In a fifth aspect, a terminal device is provided, including a processor, a memory, and a communication interface, the memory is used to store one or more computer programs, and the processor is used to call the computer programs in the memory to make the terminal device perform some or all of the steps in the method of the first aspect.

According to a sixth aspect, a network device is provided, including a processor, a memory, and a communication interface, the memory is used to store one or more computer programs, and the processor is used to call the computer programs in the memory to make the network device perform some or all of the steps in the method of the second aspect.

In a seventh aspect, the embodiment of the present application provides a communication system, where the system includes the above-mentioned terminal and/or network device. In another possible design, the system may further include other devices that interact with the terminal or network device in the solutions provided by the embodiments of the present application.

In an eighth aspect, the embodiment of the present application provides a computer-readable storage medium, the computer-readable storage medium stores a computer program, and the computer program enables the terminal to execute some or all of the steps in the method of the first aspect above.

In a ninth aspect, the embodiment of the present application provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and the computer program causes the network device to perform some or all of the steps in the method of the second aspect above.

In a tenth aspect, an embodiment of the present application provides a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, and the computer program is operable to cause a terminal to perform some or all of the steps in the method of the first aspect above. In some implementations, the computer program product can be a software installation package.

In an eleventh aspect, an embodiment of the present application provides a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, and the computer program is operable to cause a network device to perform some or all of the steps in the method of the second aspect above. In some implementations, the computer program product can be a software installation package.

In a twelfth aspect, the embodiment of the present application provides a chip, the chip includes a memory and a processor, and the processor can call and run a computer program from the memory to implement some or all of the steps described in the method of the first aspect or the second aspect above.

In the embodiment of the present application, if the first condition is met, the terminal device starts the handover condition evaluation task related to the conditional handover, and/or, if the second condition is met, the terminal device does not start or stops the handover condition evaluation task related to the conditional handover. That is to say, based on the first condition and/or the second condition, the terminal device can determine whether to enable or not to enable (or stop) the handover condition evaluation task related to the conditional handover, avoiding the traditional conditional handover mechanism, the terminal device can always perform the handover condition evaluation task related to the conditional handover based on the stored conditional handover configuration information, which is conducive to reducing the power consumed by the terminal device to perform the handover condition evaluation task related to the conditional handover, so as to improve the efficiency of the terminal device to perform the handover condition evaluation task related to the conditional handover.

Description of drawings

FIG. 1 is a schematic diagram of a dual connection architecture of an EN-DC.

FIG. 2 is a schematic diagram of a networking mode in an EN-DC dual connection scenario.

FIG. 3 is a schematic diagram of a networking mode in an EN-DC dual connection scenario.

FIG. 4 is a schematic diagram of a networking manner of a control plane in a dual connection scenario of the EN-DC.

Fig. 5 is a schematic diagram of a communication system applicable to an embodiment of the present application.

Fig. 6 is a schematic diagram of a communication method according to an embodiment of the present application.

Fig. 7 is a schematic diagram of a communication method according to another embodiment of the present application.

Fig. 8 is a schematic diagram of a terminal device according to an embodiment of the present application.

FIG. 9 is a schematic diagram of a network device according to an embodiment of the present application.

Fig. 10 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed ways

The technical solution in this application will be described below with reference to the accompanying drawings. In order to facilitate the understanding of the present application, the communication process involved in the embodiment of the present application will be introduced below with reference to FIG. 1 to FIG. 5 .

Dual connection communication scenario

The method provided in the embodiment of the present application can be used in various multi-RAT dual connectivity (multiple RAT dual connectivity, MR-DC) architectures. For example, dual connectivity between a fourth generation (4th generation, 4G) communication system and a fifth generation (5th generation, 5G) communication system, dual connectivity between a 5G communication system and a 4G communication system, or dual connectivity between a 5G communication system and a 5G communication system, etc.

The aforementioned dual connectivity between the 4G communication system and the 5G communication system may include: dual connectivity (E-UTRA-NR dual connectivity, EN-DC) between the evolved universal terrestrial radio access (E-UTRA) system and the new radio (NR) system, and dual connectivity (NG-RAN E-UTRA-N) between the E-UTRA system and the NR system under the 5G core network. R dual connectivity, NGEN-DC), etc. Among them, EN-DC can also be called option 3 series (option 3 series).

FIG. 1 is a schematic diagram of a dual connection architecture of an EN-DC. Referring to Figure 1, EN-DC uses a long term evolution (LTE) base station (such as eNB) as the master node (MN) or main base station, and an NR base station (such as gNB) as the secondary node (SN) or DC of the secondary base station, and the MN and SN can respectively establish a data plane connection with the evolved packet core (EPC) network (ie, 4G core network) to connect terminal equipment and Data between EPCs provides air interface transmission resources. Wherein, the EPC may include a mobility management node function (mobility management entity, MME) and/or a serving gateway (serving gateway, S-GW).

It should be noted that, in the architecture shown in FIG. 1 , the S1 interface is a communication interface between the LTE base station and the EPC. Based on the different types of information transmitted in the S1 interface, the S1 interface can be divided into an S1-U interface and an S1-C interface, wherein the S1-U interface can be used to transmit user plane data, and the S1-C interface can be used to transmit control plane signaling.

The following uses the two networking modes shown in Figure 2 to Figure 3 as examples to introduce the connection mode between the terminal device and the network device in the EN-DC dual connection scenario.

Referring to Figure 2, the LTE eNB acts as the MN, and establishes an S1-U interface and an S1-C interface with the EPC. As the SN, the gNB establishes an S1-U interface with the EPC. Under this architecture, the control plane signaling transmission between the EPC and the base station can only be transmitted between the EPC and the LTE eNB, and then the LTE eNB forwards the specific control plane signaling to the gNB. The user plane data can be transmitted between EPC and LTE eNB and between EPC and gNB respectively.

Referring to Figure 3, the LTE eNB acts as the MN, and establishes an S1-U interface and an S1-C interface with the EPC. As the SN, the gNB does not directly communicate with the EPC. Under this architecture, the control plane signaling and user plane data transmission between the EPC and the base station can only be transmitted between the EPC and the LTE eNB, and then the LTE eNB transmits specific control plane signaling and/or user plane data to the gNB.

It should be noted that, in the networking modes shown in FIG. 2 and FIG. 3 , both the MN and the SN can be provided with RRC entities to generate RRC PDUs, see FIG. 4 . However, at the same time, the terminal equipment usually has only one RRC state machine based on the MN side.

It should also be noted that the signaling bearers in LTE may include signaling radio bearers (signaling radio bearer, SRB) 0, SRB1, and SRB2. On this basis, EN-DC can further support SRB3. SRB3 is used to transmit the RRC signaling between the SN and the terminal equipment, and the generation of the signaling bearer does not require resource negotiation and UE capability negotiation with the MN. In addition, in order to improve the reliability of SRB1 and SRB2 transmission, EN-DC can also support split SRB1 (split SRB1) and split SRB2, that is, the packet data convergence protocol protocol data unit (PDCP PDU) corresponding to the RRC message generated by the MN is repeatedly transmitted on the SN side.

NGEN-DC can also be called option 7 series (option 7 series). In NG EN-DC, the LTE base station (such as ng-eNB) is used as the MN, and the NR base station (such as gNB) is used as the DC of the SN. Different from EN-DC, in NG EN-DC, both MN and SN can connect to 5G core network (5G core network, 5GC), providing air interface transmission resources for data between terminal equipment and 5GC.

The dual connectivity between the 5G communication system and the 4G communication system may include dual connectivity (NRE-UTRA dual connectivity, NE-DC) between the NR system and the E-UTRA system. NE-DC can also be called option 4 series (option 4 series). NE-DC uses the NR base station (such as gNB) as the MN, and the LTE base station (such as ng-eNB) as the SN, and the MN and SN can respectively have a data plane connection with the 5GC, providing air interface transmission resources for data between the terminal device and the 5GC.

The dual connection between the 5G communication system and the 5G communication system may include the NR system and the DC of the NR system. In the NR system and the DC of the NR system, both the MN and the SN are NR base stations.

The communication system to which this embodiment of the present application applies is described below by taking the communication system 50 shown in FIG. 5 as an example.

As shown in FIG. 5 , it is a schematic structural diagram of a communication system 50 provided in the embodiment of the present application. In FIG. 5 , a communication system 50 may include a network device 501 , a network device 502 , a network device 505 , a terminal device 503 and a terminal device 504 . FIG. 5 is only a schematic diagram, and does not constitute a limitation on the applicable scenarios of the technical solution provided in this application.

The network devices in FIG. 5 , that is, the network device 501 , the network device 502 or the network device 505 may be any device with a wireless transceiver function. Including but not limited to: evolved base station (evolutional Node B, NodeB or eNB or e-NodeB) in LTE, base station (gNodeB or gNB) or transmission receiving point (transmission receiving point/transmission reception point, TRP) in NR, subsequent evolution of 3GPP, etc. The base station can be: a macro base station, a micro base station, a pico base station, a small station, a relay station, or a balloon station, etc. Multiple base stations may support the aforementioned networks of the same technology, or may support the aforementioned networks of different technologies. A base station may contain one or more co-sited or non-co-sited TRPs. The network device may also be a wireless controller, a centralized unit (centralized unit, CU), and/or a distributed unit (distributed unit, DU) in a cloud radio access network (cloud radio access network, CRAN) scenario.

The terminal in FIG. 5, that is, terminal device 503 or terminal device 504, is a device with wireless transceiver function, which can be deployed on land, including indoor or outdoor, handheld, wearable or vehicle-mounted; it can also be deployed on water (such as ships, etc.); it can also be deployed in the air (such as on aircraft, balloons and satellites, etc.). The terminal may be a mobile phone, a tablet computer (Pad), a computer with a wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (augmented reality, AR) terminal device, a terminal in industrial control (industrial control), a vehicle-mounted terminal device, a terminal in self driving, a terminal in assisted driving, a terminal in remote medical (remote medical), a smart grid (smart grid). grid), terminal in transportation safety, terminal in smart city, terminal in smart home, etc. The embodiments of the present application do not limit the application scenarios. The terminal may also be sometimes referred to as terminal equipment, user equipment (UE), access terminal, vehicle-mounted terminal, industrial control terminal, UE unit, UE station, mobile station, mobile station, remote station, remote terminal, mobile device, UE terminal equipment, wireless communication equipment, machine terminal, UE agent, or UE device, etc. Terminals can be fixed or mobile.

As an example but not a limitation, in this embodiment of the application, the terminal may be a wearable device. Wearable devices can also be called wearable smart devices, which is a general term for the application of wearable technology to intelligently design daily wear and develop wearable devices, such as glasses, gloves, watches, clothing and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not only a hardware device, but also achieve powerful functions through software support, data interaction, and cloud interaction. Wearable smart devices in a broad sense include full-featured, large-sized devices that do not rely on smartphones to achieve complete or partial functions, such as smart watches or smart glasses, and those that only focus on a certain type of application function and need to be used in conjunction with other devices such as smart phones, such as smart bracelets and smart jewelry for physical sign monitoring.

cell switching

Cell handover (handover, HO) aims to improve the continuity of services provided by the communication system to terminal equipment. In a wireless communication system, when a terminal device moves from one cell (also known as a "source cell") to another cell, the terminal device needs to be handed over to another cell (also known as a "target cell") in order to maintain communication. Wherein, the cell may be a primary cell (primary cell, PCell) or a primary secondary cell (primary secondary cell, PSCell). Generally, cell handover can be divided into two types: traditional handover mechanism and conditional handover mechanism.

For the traditional handover mechanism, in order to improve the continuity of services provided by the communication system to terminal devices in the connected state, the network device will send a handover command to the terminal device at an appropriate time (for example, the signal measurement result of the terminal device in the serving cell is lower than the threshold) to instruct the terminal device to perform cell handover. In some implementation manners, the above handover command may be an RRC reconfiguration message including synchronous reconfiguration information.

For a conditional handover (conditional handover, CHO) mechanism, the network device can configure the configuration of one or more target cells and the conditional handover events associated with one or more conditional handover target cells to the terminal device, and accordingly, the terminal device can perform a handover condition evaluation task to evaluate whether the conditional handover events associated with the above one or more conditional handover target cells are satisfied. When one or more conditional handover events associated with the above one or more conditional handover target cells are met, the terminal device can handover from the source cell (or "current serving cell") to the corresponding conditional handover target cell that satisfies the conditional handover event. Currently, the above conditional switching mechanism can be applied to the scenario of adding a conditional PSCell, the scenario of changing a conditional PSCell, and the scenario of changing a conditional PCell. It should be noted that, in the scenario where the conditional PSCell is added and/or the scenario where the conditional PSCell is changed, the above-mentioned conditional handover target cell is the target PSCell, and the source cell is the source PSCell. In the scenario where the conditional PCell is changed, the above-mentioned conditional handover target cell is the target PCell, and the source cell is the source PCell.

In a conditional primary and secondary cell addition/change (conditional PSCell addition/change, CPAC) scenario, the source PCell or the source PSCell sends conditional handover configuration information to the terminal device, wherein the conditional handover configuration information includes configuration information of at least one conditional added/changed target PSCell cell and handover condition configuration information associated with each conditional added/changed target PSCell cell. Correspondingly, after the terminal device successfully executes the conditional handover based on the handover configuration message, the terminal device will delete all saved configuration information of the conditional addition/change target PSCell and the conditional handover configuration information of each conditional addition/change target PSCell. Wherein, the terminal device executes the conditional handover successfully based on the handover configuration message, which can be understood as the terminal device successfully accesses a conditional handover target PSCell.

In the scenario where the conditional PCell is changed, the source PCell may send conditional handover configuration information to the terminal device, where the conditional handover configuration information includes configuration information of at least one conditional handover target PCell cell and conditional handover configuration information associated with each conditional handover target PCell cell. Correspondingly, after the terminal device successfully executes the conditional handover based on the handover configuration message, the terminal device deletes all previously saved configuration information of the conditional handover target PCell and the conditional handover configuration associated with each conditional handover target PCell. Wherein, the terminal device executes the conditional handover successfully based on the handover configuration message, which can be understood as the terminal device successfully accesses a conditional handover target PCell.

In some implementations, the above conditional handover configuration information includes configuration information associated with at least one conditional handover target cell, wherein the configuration information associated with any conditional handover target cell in the at least one conditional handover target cell may include one or more of configuration parameter 1, configuration parameter 2, and configuration parameter 3.

The configuration parameter 1 includes a logical identification ID, which is used to identify a logical number of a CHO configuration, a CPA configuration or a CPC configuration. In some implementation manners, the above configuration parameter 1 may include a parameter CondReconfigId.

The configuration parameter 2 includes configuration information of the conditional handover target cell, and the terminal device can switch to the conditional handover target cell based on the configuration information of the conditional handover target cell. In some implementations, the above configuration parameter 2 may include one or more of the following configuration information: physical layer configuration that the terminal needs to use in the conditional handover target cell, media access control (media access control, MAC) layer configuration that the terminal needs to use in the conditional handover target cell, radio link control (radio link control, RLC) layer configuration that the terminal needs to use in the conditional handover target cell, data radio bearer (data radio bearer, DRB) related configuration that the terminal needs to use in the conditional handover target cell, conditional handover Configuration related to the frequency band and bandwidth supported by the target cell and random access configuration.

Configuration parameter 3: switching condition configuration. In some implementation manners, the configuration parameter 3 may include at least one measurement ID, and a measurement ID is associated with a measurement object (measurement object, MO) configuration and a measurement report configuration (report configuration). In some implementations, the above measurement reporting configuration may include a conditional handover event, which is used by the terminal device to determine whether to trigger handover to the conditional handover target cell associated with the conditional handover event. Therefore, the conditional handover event may also be called "conditional handover trigger condition" or "conditional handover-related handover condition".

In some other implementation manners, the condition switching event type of the condition switching event may include at least one of a condition A3 event, a condition A4 event, a condition A5 event, a D1 event, and a T1 event.

The condition A3 event includes that the measurement result of the conditional handover target cell is higher than the measurement result of the current serving cell where the terminal device is located, and the difference between the measurement result of the conditional handover target cell and the measurement result of the current serving cell is greater than or equal to the first threshold.

The condition A4 event includes the condition that the measurement result of the handover target cell is greater than or equal to the second threshold.

The condition A5 event includes that the measurement result of the current serving cell where the terminal device is located is lower than the third threshold, and the measurement result of the conditional handover target cell is higher than the fourth threshold.

The condition D1 event includes that the distance between the terminal device and the location reference point 1 is greater than the fifth threshold, and the distance between the terminal device and the location reference point 2 is smaller than the sixth threshold.

The conditional T1 event includes that the local time of the terminal device exceeds the configured time 1 but does not exceed the configured time 2 , where time 2 is later than time 1 .

In some implementation manners, one conditional handover target cell may only be associated with one conditional handover event configuration information, that is, the configuration parameter 3 associated with one conditional handover target cell includes only one measurement ID.

In some other implementation manners, a conditional handover target cell may be associated with at least two conditional handover event configuration information, or in other words, the configuration parameter 3 associated with a conditional handover target cell includes at least two measurement IDs. At this time, the conditional handover event associated with the conditional handover target cell satisfies two situations. In case 1, at least two conditional handover events corresponding to the conditional handover event configuration information are satisfied (or triggered) before the handover condition associated with the conditional handover target cell is considered to be satisfied. In case 2, if at least one of the conditional handover events corresponding to at least two conditional handover event configuration information is satisfied, it is considered that the handover condition event associated with the conditional handover target cell is satisfied.

It should be noted that one or more parameters of the above-mentioned first threshold, second threshold, third threshold, fourth threshold, fifth threshold, sixth threshold, time 1 and time 2 may be configured by the network device to the terminal device, for example, the network device may be configured through a system broadcast message or dedicated signaling.

In some implementation manners, the configuration format at the above moment 2 may include two types. In configuration format 1, time 2 can be universal time coordinated (UTC) time. For example, the configuration format of time 2 can be in the format of year, month, day, hour, minute, and second, that is, 2021.11.25 17:43:05. In configuration format 2, time 2 may be determined based on time 1. For example, time 2 may be a time that starts from time 1 and elapses after a fixed duration, that is, time 2 is a time corresponding to 20 seconds after time 1. Of course, the above moment 2 may also adopt other configuration formats.

It is introduced above that the terminal device can perform handover condition evaluation tasks related to conditional handover to evaluate whether the conditional handover events associated with the above one or more conditional handover target cells are satisfied. In some implementations, if the conditional handover configuration information stored by the terminal device includes handover condition configuration information associated with multiple conditional handover target cells, then the terminal device starts the handover condition evaluation task related to the conditional handover, which can be understood as the terminal device needs to evaluate the conditional handover events associated with each conditional handover target cell (that is, the conditional handover event contained in the configuration parameter 3 associated with each conditional handover target cell) to determine whether each conditional handover target cell is satisfied. Assessment tasks. Correspondingly, the terminal device does not perform the handover condition evaluation task can be divided into two situations. In the first case, the terminal device stops the handover condition evaluation task, that is, the terminal device originally executes (or starts) the handover condition evaluation task, but due to some reasons (for example, in the case of satisfying the second condition hereinafter), the terminal device stops the handover condition evaluation task. In the second case, the terminal device does not start the handover condition evaluation task, that is, the terminal device has not performed the above handover condition evaluation task.

For ease of understanding, the conditional switching will be introduced below by taking the CPAC process as an example in conjunction with FIG. 5 . It should be noted that the process of changing the conditional PCell is similar to the CPAC process, and will not be introduced separately for brevity. In addition, in order to facilitate the distinction between the conditional handover target PSCell included in the conditional handover configuration and the conditional handover target PSCell that the terminal device switches to after conditional handover, hereinafter, the conditional handover target PSCell included in the conditional handover configuration is called a "candidate PSCell", and the conditional handover target PSCell that the terminal device is switched to after a conditional handover is called a "target PSCell".

In FIG. 5 , terminal device 503 or terminal device 504 can be dual-connected to network device 505 and network device 502, wherein one network device is MN and the other network device is SN. One or more serving cells in the MN belong to a master cell group (MCG). Generally, the MCG may include a primary cell (PCell). In some implementation manners, in addition to the PCell, the MCG may also include one or more secondary cells (secondary cell, SCell). One or more serving cells in the SN belong to a secondary cell group (SCG). Generally, a PSCell may be included in an SCG. In some implementation manners, the SCG may include one or more SCells in addition to the PSCell.

In the communication system 50 shown in FIG. 5 , the terminal device 503 or the terminal device 504 can perform CPAC. For example, the terminal device 503 can perform conditional PSCell addition (conditional PSCell addition, CPA) through the following example 5, and perform conditional PSCell change (conditional PSCell change, CPC) through the following example 2.

Example 5, taking terminal device 503 to establish an RRC connection with network device 501, terminal device 503 needs to perform CPA, and establish a connection with network device 502 as an example, after network device 501 establishes an RRC connection with terminal device 503, one or more candidate PSCells can be configured for terminal device 503 (that is, the PSCell condition addition described above: CPA), and the one or more candidate PSCells include the PSCell configured by network device 502 for terminal device 503 and other network devices as terminal devices 503 configured PSCell; the network device 501 sends the configuration information 1 of the one or more candidate PSCells to the terminal device 503, and the configuration information 1 of the candidate PSCell includes the configuration 1 and the addition condition of the candidate PSCell (ie, the switching condition configuration information introduced above). The terminal device 503 receives the configuration information 1 of the one or more candidate PSCells from the network device 501, and can detect the addition condition associated with the one or more candidate PSCells. When at least one candidate PSCell meeting the addition condition is detected, the terminal device 503 selects one of the candidate PSCells (such as the candidate PSCell configured by the network device 502 for the terminal), and applies the configuration of the candidate PSCell. Subsequently, the terminal device 503 initiates random access with the candidate PSCell, and establishes a dual connection with the network device 502 after the random access of the candidate PSCell succeeds. The configuration information 1 of the candidate PSCell may also be called the CPA configuration information 1 of the candidate PSCell or the CPA-related conditional handover configuration information of the candidate PSCell, and the name of the configuration information is not limited in this embodiment of the present application.

It can be understood that, when the terminal device 503 detects multiple candidate PSCells meeting the addition condition, it may select a candidate PSCell according to a preset strategy, and apply the configuration of the candidate PSCell. For example, when the terminal device 503 detects a plurality of candidate PSCells satisfying the addition condition, it may randomly select a candidate PSCell and apply the configuration of the candidate PSCell; or, among the plurality of candidate PSCells satisfying the addition condition, select the candidate PSCell with the best signal quality and apply the configuration of the candidate PSCell; ell's configuration. The foregoing is only an example of selecting a candidate PSCell by the terminal device 503, and the terminal device 503 may also select a candidate PSCell in other ways, which is not limited.

Example 2, take the terminal device 503 to establish a dual connection with the network device 501 and the network device 502, the network device 501 is the MN, the network device 502 is the SN, and the terminal device 503 wants to perform CPC as an example, the network device 505 can configure one or more candidate PSCells for the terminal device 503 through the network device 501 or the network device 502 (that is, the PSCell condition change described above); the network device 501 or the network device 502 sends the one or more candidate PSCells to the terminal device 503 The configuration information 2 of the PSCell and the configuration information 2 of the candidate PSCell include the configuration 2 and the change condition of the candidate PSCell (ie, the switching condition configuration information introduced above). The terminal device 503 receives the configuration information 2 of the one or more candidate PSCells from the network device, and may detect the change condition of the one or more candidate PSCells, and when at least one candidate PSCell meeting the change condition is detected, the terminal device 503 selects one of the candidate PSCells, and applies the configuration of the candidate PSCell. Subsequently, the terminal device 503 initiates random access with the candidate PSCell, and establishes a dual connection with the network device 501 and the SeNB to which the candidate PSCell belongs after the random access to the candidate PSCell succeeds. Wherein, the configuration information 2 of the candidate PSCell may also be called the CPC configuration information 2 of the candidate PSCell, or may also be called the CPC-related conditional switching configuration information of the candidate PSCell, without limitation.

It can be understood that when the terminal device 503 detects multiple candidate PSCells meeting the change condition, it may select a candidate PSCell according to a preset policy, and apply the configuration of the candidate PSCell. For example, when the terminal device 503 detects a plurality of candidate PSCells meeting the change condition, it may randomly select a candidate PSCell and apply the configuration of the candidate PSCell; or, among the plurality of candidate PSCells meeting the change condition, select the candidate PSCell with the best signal quality and apply the configuration of the candidate PSCell; ell's configuration. The foregoing is only an example of selecting a candidate PSCell by the terminal device 503, and the terminal device 503 may also select a candidate PSCell in other ways, which is not limited.

It should be noted that, in this embodiment of the present application, for any candidate PSCell among the one or more candidate PSCells configured by any network device for the terminal, when the terminal performs CPA, the configuration information 1 of the candidate PSCell, and when the terminal performs CPC, the configuration information 2 of the candidate PSCell can be collectively referred to as the configuration information associated with the candidate PSCell (or the conditional handover configuration information of the conditional handover target cell). The configuration of ell (that is, the configuration parameter 2 mentioned above: the configuration information of the conditional handover target cell). The configuration information associated with the candidate PSCell includes the configuration of the candidate PSCell (ie, the configuration parameter 2 mentioned above) and the conditions for adding/changing PSCell cells associated with the candidate PSCell (ie, the configuration parameter 3 mentioned above). Wherein, when the terminal performs CPA, the configuration of the candidate PSCell is used for communicating with the candidate PSCell when the terminal device prepares to add the candidate PSCell, the adding/changing conditions of the candidate PSCell include the adding condition of the candidate PSCell, and the adding condition of the candidate PSCell is used for the terminal device to determine whether the candidate PSCell can be added. When the terminal performs CPC, the configuration of the candidate PSCell is used by the terminal device to communicate with the candidate PSCell when it is preparing to change the source PSCell to the candidate PSCell. The addition/change conditions of the candidate PSCell include the change conditions of the candidate PSCell. The change conditions of the candidate PSCell are used by the terminal device to determine whether the source PSCell can be changed to the candidate PSCell.

When the terminal device 503 has received the configuration and addition/change conditions of one or more candidate PSCells, but has not detected a PSCell that satisfies the addition/change conditions, the terminal device 503 can also switch from the current MN to a target MN with better signal quality, for example, the terminal device 503 can switch from the network device 501 to the network device 505. Usually, after the terminal device 503 performs MN switching, the current MN will release one or more candidate PSCells configured for the terminal device 503. After the target MN establishes an RRC connection with the terminal device 503, it can reconfigure one or more candidate PSCells for the terminal device 503, and send the configuration information of one or more candidate PSCells configured by the target MN for the terminal to the terminal device 503 for the terminal to perform CPAC. The configuration information of one or more candidate PSCells configured by the target MN for the terminal includes the candidate PSCell Configure and add/change conditions.

As mentioned above, regardless of the conditional handover in any scenario, when the terminal device successfully executes the conditional handover based on the conditional handover configuration information provided by the network device, the terminal device will release (or delete) the corresponding conditional handover configuration information. When the terminal device needs to perform the next conditional switching, the network device needs to provide the terminal device with conditional switching configuration information again. In this way, the overhead required for the network device to transmit conditional switching configuration information will be increased. However, it is actually unnecessary for the network device to re-provide the conditional switching configuration information for the terminal device during each round of conditional switching of the terminal device. Because in some cases, the conditional handover configuration information used by the terminal device for conditional handover may be the same. For example, when the terminal device moves within a small range, the configuration content of the conditional handover configuration information used by the terminal device for each round of conditional handover is the same.

Therefore, in order to reduce the overhead occupied by transmitting conditional switching configuration information, a continuous conditional switching process can be adopted, that is, the terminal device can perform multiple rounds of conditional switching based on the conditional switching configuration information configured once by the network device. In this way, the network device does not need to re-provide the conditional switching configuration information for the terminal device during each round of conditional switching, which helps reduce the overhead occupied by transmitting the conditional switching configuration information.

In some implementation manners, the terminal device may perform multiple rounds of conditional handover based on the same conditional handover configuration information within a period of time. The period of time can be predefined or preconfigured. In other implementation manners, when the first condition is satisfied, the terminal device may perform multiple rounds of conditional handover based on the same conditional handover configuration information. Wherein, the first condition may be, for example, that the movement range of the terminal device is smaller than a threshold. Certainly, the embodiment of the present application does not specifically limit the content of the first condition. In addition, the foregoing first condition may be configured by the network, and the foregoing first condition may also be predefined.

It should be noted that, in the above continuous conditional handover process, the conditional handover configuration message used by the terminal device can be understood to be configured by the historical serving cell of the terminal device. Wherein, the historical serving cell is a serving cell that the terminal device is currently connected to or a cell that provided services to the terminal device before the serving cell to which the terminal device is currently connected.

In addition, when the terminal device performs conditional handover based on the conditional handover configuration information, if the terminal device fails to access the conditional handover target cell, the terminal device may not delete the above conditional handover configuration information, but continue to execute the handover condition evaluation task related to the conditional handover, so as to continue to evaluate whether the conditional handover event associated with the conditional handover target cell included in the conditional handover configuration information is satisfied. For example: it is used in the scenario of fast recovery of cell connection after the conditional handover of the terminal device fails. Although the conditional handover fails, the terminal device still stores the configuration information of one or more conditional handover target cells.

It should be noted that, in the above scenario where the terminal device fails to access the conditional handover target cell, the conditional handover configuration message used by the terminal device can be understood as being configured by the historical serving cell of the terminal device. Wherein, the historical serving cell is a serving cell that the terminal device is currently connected to or a cell that provided services to the terminal device before the serving cell to which the terminal device is currently connected.

Regardless of the continuous conditional handover scenario described above, or the scenario where the terminal device fails to access the conditional handover target cell, if the terminal device does not delete the stored conditional handover configuration information, the terminal device needs to further consider how to perform subsequent handover condition evaluation tasks related to conditional handover to evaluate whether it meets the conditional handover events associated with one or more conditional handover cells contained in the above conditional handover configuration information, and determine whether to switch to the corresponding conditional handover target cell based on the evaluation results. The terminal device will consume a certain amount of power when performing the handover condition evaluation tasks related to the conditional handover in each round. If the terminal equipment is always based on the stored conditional handover configuration information and executes the handover conditional tasks related to the conditional handover, it will reduce the efficiency of the terminal equipment to perform the handover condition evaluation tasks related to the handover conditions, because in some cases it is unnecessary to enable the handover condition evaluation tasks related to the handover conditions.

Therefore, in order to improve the efficiency of the terminal device in performing handover condition evaluation tasks related to conditional handover, the present application provides a communication method. In the following, in conjunction with FIG. 6 , the communication method of the embodiment of the present application is introduced by taking the terminal device evaluating whether the conditional handover event associated with the first conditional handover target cell is satisfied as an example, wherein the first conditional handover target cell can be understood as one of the one or more conditional handover target cells corresponding to the conditional handover configuration information. In addition, the one or more conditional handover target cells corresponding to the conditional handover configuration information may be understood as the target cells to which the terminal device may handover, that is, the above candidate target cells. The communication method shown in FIG. 6 includes step S610 and/or step S620.

In step S610, if the first condition is met, the terminal device starts a handover condition evaluation task related to conditional handover.

The handover condition evaluation task related to the above conditional handover is used to evaluate whether the conditional handover event associated with the first conditional handover target cell is satisfied.

It should be noted that, in the above continuous conditional handover scenario, the first conditional handover target cell can be understood as one of the conditional handover target cells to which the terminal device performs at least one conditional handover based on the conditional handover configuration information. In the scenario where the terminal device fails to access the conditional handover target cell, the above-mentioned first conditional handover target cell can be understood as a cell where the terminal device attempts to restore the PCell or PSCell connection based on the conditional handover configuration information. In general, the difference between the first conditional handover target cell in the above two scenarios can be understood as: in the continuous conditional handover scenario, the terminal device successfully switches to the first conditional handover target cell through conditional handover, or in other words, in the continuous conditional handover scenario, the terminal device successfully accesses the first conditional handover target cell.

It should be understood that in the continuous conditional switching scenario, since the conditional switching configuration information stored by the terminal device is not deleted after the conditional switching is successful, it can be reused by the terminal device, thereby realizing the purpose of configuring the conditional switching configuration information once on the network device, and the terminal device can perform multiple conditional switching.

In the scenario where the conditional handover target cell is not successfully accessed, the network device configures the conditional handover configuration information once, and the terminal device can perform multiple conditional handovers. This is to prevent the terminal device from restoring the PCell or PSCell cell connection through the connection re-establishment process or the connection reconfiguration process after a conditional handover fails, resulting in a long delay for the terminal device to restore the PCell or PSCell cell connection. In the above scenario, the terminal device can try to directly restore the PCell or PSCell cell connection based on the stored conditional switching configuration information, which is not only beneficial for the terminal device to quickly restore the PCell or PSCell cell connection, but also does not require the network device to frequently send reconfiguration messages.

In step S620, if the second condition is satisfied, the terminal device does not start or stops the handover condition evaluation task related to conditional handover.

If the above-mentioned second condition is satisfied, the terminal device stops the handover condition evaluation task related to the conditional handover. It can be understood that the terminal device originally starts (or executes) the handover condition evaluation task related to the conditional handover, but because the second condition is met, the terminal device no longer executes the handover condition evaluation task related to the conditional handover. In other words, within a period of time before the second condition is met, the terminal device performs a handover condition evaluation task related to conditional handover. When the second condition is met, the terminal device stops handover condition evaluation tasks related to conditional handover.

If the above second condition is met, the terminal device does not start the handover condition evaluation task related to the conditional handover. It can be understood that the terminal device does not start the handover condition evaluation task related to the conditional handover before the second condition is met. And after the second condition is satisfied, the terminal device does not start the handover condition evaluation task related to the conditional handover.

It should be noted that the above step S610 and step S620 can be used independently. For example, if the first condition is satisfied, the terminal device starts the handover condition evaluation task related to the conditional handover; on the contrary, if the first condition is not met, the terminal device does not start or stops the handover condition evaluation task related to the conditional handover. For another example, when the second condition is satisfied, the terminal device does not start or stop the handover condition evaluation task related to the conditional handover. If the second condition is not met, the terminal device starts a handover condition evaluation task related to conditional handover. Of course, as mentioned above, the above step S610 and step S620 may also be used in combination.

In the embodiment of the present application, if the first condition is met, the terminal device starts the handover condition evaluation task related to the conditional handover, and/or, if the second condition is met, the terminal device does not start or stops the handover condition evaluation task related to the conditional handover. That is to say, based on the first condition and/or the second condition, the terminal device can determine whether to enable or not to enable (or stop) the handover condition evaluation task related to the conditional handover, which avoids the terminal device from always performing the handover condition evaluation task related to the conditional handover, helps to reduce the power consumed by the terminal device to perform the handover condition evaluation task related to the conditional handover, and improves the evaluation efficiency of the terminal device to perform the handover condition evaluation task.

A possible implementation manner of the first condition applicable to the embodiment of the present application is introduced below. It should be noted that the implementation manners listed below for the first condition may be used alone or in combination, which is not limited in this embodiment of the present application.

Implementation manner 1, the first condition includes that the terminal device successfully receives a reconfiguration message (also called "the first reconfiguration message") sent by the network device.

Wherein, the first reconfiguration message may carry conditional handover configuration information, or may not carry conditional handover configuration information. For ease of distinction, the conditional handover configuration information in the first reconfiguration message is called "conditional handover configuration information 2", and correspondingly, the conditional handover configuration information originally stored in the terminal device is called "conditional handover configuration information 1".

In some implementations, the above-mentioned first reconfiguration message is used to trigger the terminal device to perform timely handover (relative to conditional handover). In this scenario, the first reconfiguration message does not carry conditional handover configuration information, and the terminal device starts handover condition evaluation tasks related to conditional handover when it successfully receives the first reconfiguration message.

In some other implementation manners, the foregoing first reconfiguration message is used to trigger the terminal device to update the configuration of the current serving cell of the terminal device (for example, in a non-handover scenario). Usually, in this case, the first reconfiguration message does not carry conditional handover configuration information. When the terminal device successfully receives the first reconfiguration message, it starts a handover condition evaluation task related to conditional handover

In some other implementation manners, the first reconfiguration message is used to trigger the terminal device to perform operations related to conditional handover, where performing operations related to conditional handover includes at least one of adding, modifying, or deleting configuration information of conditional handover. In this scenario, the above-mentioned first reconfiguration message will include conditional handover configuration information 2, wherein the conditional handover configuration information 2 included in the first reconfiguration message may be the same as or different from the conditional handover configuration information 1 stored in the terminal device above. When the terminal device successfully receives the first reconfiguration message, it starts a handover condition evaluation task related to conditional handover.

Implementation manner 2, the first condition includes that the terminal device is not successfully handed over to the handover target cell of the second condition.

The above-mentioned second conditional handover target cell belongs to at least one conditional handover target cell, or in other words, the second conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information stored in the terminal device.

The unsuccessful handover of the terminal device to the second conditional handover target cell may be caused by one or more of the following reasons: the handover timer expires, the number of random access attempts reaches the maximum number of retransmissions, and the handover completion message fails to be sent.

If the terminal device needs to access the second conditional handover target cell, the terminal device needs to successfully access the second conditional handover target cell before the handover timer times out. If the handover timer expires and the terminal device still fails to access the second conditional handover target cell, the terminal device fails to access the second conditional handover target cell. Wherein, the switching timer may be, for example, a timer T304.

If the terminal device needs to access the second conditional handover target cell, the terminal device needs to initiate random access in the second conditional handover target cell. When the number of random access attempts initiated by the terminal device reaches the maximum number of retransmissions, the terminal device fails to access the second conditional handover target cell.

If the terminal device needs to access the second conditional handover target cell, the terminal device needs to send a handover completion message to the second conditional handover target cell to indicate that the handover of the second conditional handover target cell is completed. When the terminal device fails to send a handover completion message to the second conditional handover target cell, it is considered that the terminal device fails to access the second conditional handover target cell.

In the embodiment of the present application, there are many reasons why the terminal device fails to be handed over to the second conditional handover target cell, which is not specifically limited in the embodiment of the present application.

In the embodiment of the present application, if the implementation mode 2 of the first condition is satisfied, the terminal device can start the handover condition evaluation task related to the conditional handover, so that the terminal device can continue to evaluate the suitable conditional handover target cell by starting the handover condition evaluation task related to the conditional handover after a conditional handover failure, so as to initiate the conditional handover again, which is beneficial to reduce the recovery time of the terminal device after the conditional handover fails. In the traditional conditional handover mechanism, when the terminal device fails to switch to the target cell of the conditional handover, the terminal device needs to initiate a connection re-establishment or trigger a network device reconfiguration process to restore the cell connection of the terminal device (the cell where the connection is restored can be a conditional handover cell or an unconditional handover cell, which can be to restore the PCell connection or restore the PSCell connection), resulting in a long time for the terminal device to restore the cell connection after the conditional handover fails.

Implementation mode 3: the first condition includes that the terminal equipment is successfully handed over to the handover target cell of the third condition.

The above-mentioned third conditional handover target cell belongs to at least one conditional handover target cell, or in other words, the third conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information stored in the terminal device.

The successful handover of the terminal device to the third conditional handover target cell can be understood as that the terminal device can communicate with other communication devices (eg, the network device to which the third conditional handover target cell belongs) through the third conditional handover target cell. In some implementation manners, if the terminal device successfully completes the random access process with the third conditional handover target cell before the handover timer times out, it may be understood that the terminal device successfully accesses the third conditional handover target cell. In other implementation manners, if the terminal device successfully completes uplink synchronization with the third conditional handover target cell before the handover timer times out, it may be understood that the terminal device successfully accesses the third conditional handover target cell. In some other implementation manners, before the handover timer times out, the terminal device successfully sends a reconfiguration complete message to the third conditional handover target cell, which can be understood as the terminal device successfully accessing the third conditional handover target cell. In some other implementation manners, if the terminal device successfully exchanges user data with the third conditional handover target cell, it may be understood that the terminal device successfully accesses the third conditional handover target cell. In some other implementation manners, if the terminal device successfully receives the first user data scheduling authorization instruction sent by the third conditional handover target cell, it may be understood that the terminal device successfully accesses the third conditional handover target cell. The foregoing scheduling grant instruction may include resource configuration for uplink data and/or resource configuration for downlink data, where the resource configuration may include time-frequency resource configuration.

In this embodiment of the present application, when the implementation mode 3 of the above-mentioned first condition is met, the terminal device can start the handover condition evaluation task related to the conditional handover, which may include that the terminal device does not need to start the handover condition evaluation task related to the conditional handover during the process of the terminal device trying to access the third conditional handover target cell. After the terminal device successfully switches to the third conditional handover target cell, the terminal device starts the handover condition evaluation task related to the conditional handover. It prevents the terminal device from performing handover condition evaluation tasks related to conditional handover during the process of accessing the third conditional handover target cell, and reduces the complexity of terminal device implementation during the conditional handover process (the terminal device does not need to perform handover condition evaluation tasks related to conditional handover access and conditional handover at the same time).

Implementation mode 4: the first condition includes enabling the neighbor cell measurement task of the terminal device.

Usually, in order to assist terminal equipment mobility control, a network device configures neighbor cell measurement for a terminal equipment in a connected state. The network device may determine whether to send the handover configuration to the terminal device based on the measurement result reported by the terminal device, so as to configure the terminal device to switch to the neighboring cell. In general, the terminal device needs to meet the measurement enablement condition to enable (or execute) the neighboring cell measurement task, where the measurement enablement condition may include, for example, that the measurement result (eg, signal quality) of the current serving cell measured by the terminal device is less than a threshold.

The setting of the measurement enabling condition above is to prevent the terminal equipment located in the center of the cell from performing unnecessary adjacent cell measurements, resulting in high power consumption of the terminal equipment. Therefore, when the above measurement enablement conditions are satisfied, it can be considered that the terminal device is not located in the center of the current serving cell, and needs to perform a neighboring cell measurement task.

Based on the neighbor cell measurement task introduced above, it can be seen that when the terminal device's neighbor cell measurement task is enabled, it means that the current serving cell of the terminal device cannot provide better signal quality for the terminal device, or it can be considered that the terminal device may not be located in the center of the current serving cell at this time. Therefore, in order to improve the continuity of communication of the terminal device, in the embodiment of the present application, the adjacent cell measurement task of the terminal device may be enabled as a condition for triggering the terminal device to start the handover condition evaluation task related to condition handover.

In this embodiment of the present application, based on the setting of the implementation mode 4 of the above-mentioned first condition, it is possible to prevent terminal devices with better signal quality from performing handover condition evaluation tasks related to conditional handover, or in other words, to prevent terminal devices in the center of the current serving cell from performing handover condition evaluation tasks related to conditional handover, which is conducive to improving the efficiency of terminal devices performing handover condition evaluation related to conditional handover, and avoiding unnecessary handover condition evaluation tasks related to conditional handover.

In addition, in the embodiment of the present application, the activation of the adjacent cell measurement task of the terminal device is used as the first condition to determine the handover condition evaluation task related to the conditional handover, that is, the measurement enablement condition of the neighbor cell measurement task specified in the known communication protocol is reused as the condition for the terminal device to enable the handover condition evaluation task related to the conditional handover, which is beneficial to reduce the application of the method of the embodiment of the application. Changes to existing communication protocols improve the compatibility of the method of the embodiment of this application with existing communication systems.

Implementation manner 5: The signal measurement result of the serving cell measured by the terminal device is less than or equal to the first threshold.

The foregoing signal measurement result may indicate the service quality of the service provided by the current serving cell to the terminal device. In some implementation manners, the foregoing signal measurement results may include cell-level measurement results and/or beam-level measurement results, where the cell-level measurement results may be understood as measurement results with a granularity of a cell. Measurement results at the beam level can be understood as measurement results at the granularity of beams. In some other implementation manners, the measurement quantity corresponding to the above signal measurement result may be any one of RSRP, RSRQ or SINR.

It should be noted that the above first threshold may be configured for the terminal device in a pre-configuration manner, a default configuration manner, a system broadcast message manner, or a dedicated signaling manner, which is not limited in this embodiment of the present application.

In the embodiment of the present application, based on the setting of the implementation mode 5 of the above-mentioned first condition, it is possible to prevent terminal devices with better signal measurement results (for example, better signal quality) from starting handover condition evaluation tasks related to conditional handover, or to prevent terminal devices in the center of the current serving cell from starting handover condition evaluation tasks related to conditional handover, which is conducive to improving the efficiency of terminal devices in performing handover condition evaluation tasks related to conditional handover, and avoiding starting unnecessary handover condition evaluation tasks related to conditional handover.

In addition, in the embodiment of the present application, the signal measurement result of the serving cell is less than or equal to the first threshold as the first condition to determine the handover condition evaluation task related to conditional handover.

As mentioned above, the implementation modes 1 to 5 of the first condition above can be used alone or in combination with each other. Since there are many combinations of the five implementations of the above-mentioned first condition, for the sake of brevity, details will not be repeated below. For ease of understanding, only a few combinations are illustrated below.

In the combination mode 1, the realization mode 1 of the first condition and the realization mode 5 of the first condition may be combined, or the first condition includes the realization mode 1 and the realization mode 5. At this time, in the case that the realization mode 1 of the first condition and the realization mode 5 of the first condition are satisfied at the same time, the terminal device starts a switching condition evaluation task related to condition switching. The simultaneous satisfaction of the first condition 1 and the first condition 5 may include that the terminal device successfully receives the first reconfiguration message, and the signal measurement result of the serving cell measured by the terminal device is less than or equal to the first threshold.

In the combination mode 2, the realization mode 3 of the first condition and the realization mode 5 of the first condition may be combined, or the first condition includes the realization mode 3 and the realization mode 5. At this time, in the case that the realization mode 3 of the first condition and the realization mode 5 of the first condition are satisfied at the same time, the terminal device starts a switching condition evaluation task related to condition switching. Wherein, the simultaneous fulfillment of the first condition 3 and the first condition 5 may include that the terminal device is successfully handed over to the third conditional handover target cell, and the signal measurement result of the current serving cell (ie, the third conditional handover target cell) measured by the terminal device is less than or equal to the first threshold.

A possible implementation manner of the second condition applicable to the embodiment of the present application is introduced below. It should be noted that the implementation manners of the second condition listed below may be used alone or in combination, which is not limited in this embodiment of the present application.

Implementation manner 1, the second condition includes that the terminal device successfully receives the reconfiguration message (also called "the second reconfiguration message") sent by the network device.

Wherein, the second reconfiguration message may carry conditional handover configuration information, or may not carry conditional handover configuration information. For ease of distinction, the conditional handover configuration information in the second reconfiguration message is called "conditional handover configuration information 2", and correspondingly, the conditional handover configuration information originally stored in the terminal device is called "conditional handover configuration information 1".

Usually, after the terminal device successfully receives the second reconfiguration message, it can be understood that the conditional handover configuration information stored by the terminal device is invalid or unavailable. At this time, the terminal device can stop or not start the handover condition evaluation task related to the conditional handover based on the stored conditional handover configuration information.

In some implementations, the above-mentioned second reconfiguration message is used to trigger the terminal device to perform timely handover (relative to conditional handover). In this scenario, the second reconfiguration message does not carry conditional handover configuration information, and the terminal device stops or does not start the handover condition evaluation task related to conditional handover when successfully receiving the second reconfiguration message.

In some other implementation manners, the second reconfiguration message is used to trigger the terminal device to update the configuration of the current serving cell of the terminal device (for example, in a non-handover scenario). Usually, in this case, the second reconfiguration message does not carry conditional handover configuration information. When the terminal device successfully receives the second reconfiguration message, it stops or does not start the handover condition evaluation task related to the conditional handover.

In some other implementation manners, the second reconfiguration message is used to trigger the terminal device to perform operations related to conditional handover, where performing operations related to conditional handover includes at least one of adding, modifying, or deleting configuration information of conditional handover. At this time, the above-mentioned second reconfiguration message will include conditional handover configuration information 2, wherein the conditional handover configuration information 2 included in the second reconfiguration message may be the same as or different from the above conditional handover configuration information 1 stored in the terminal device. When the terminal device successfully receives the second reconfiguration message, it stops or does not start the handover condition evaluation task related to the conditional handover.

Implementation manner 2, the second condition includes that the terminal device fails to handover to the handover target cell of the fourth condition.

The fourth conditional handover target cell belongs to at least one conditional handover target cell, or in other words, the fourth conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information stored in the terminal device.

The unsuccessful handover of the terminal device to the fourth conditional handover target cell may be caused by one or more of the following reasons: the handover timer expires, the number of random access attempts reaches the maximum number of retransmissions, and the handover completion message fails to be sent.

If the terminal device needs to access the fourth conditional handover target cell, the terminal device needs to successfully access the fourth conditional handover target cell before the handover timer times out. If the handover timer expires and the terminal device still fails to access the fourth conditional handover target cell, the terminal device fails to access the fourth conditional handover target cell. Wherein, the switching timer may be, for example, a timer T304.

If the terminal device needs to access the fourth conditional handover target cell, the terminal device needs to initiate random access in the fourth conditional handover target cell. When the number of random access attempts initiated by the terminal device reaches the maximum number of retransmissions, the terminal device fails to access the handover target cell under the fourth condition.

If the terminal device needs to access the fourth conditional handover target cell, the terminal device needs to send a handover completion message to the fourth conditional handover target cell to indicate that the handover of the fourth conditional handover target cell is completed. When the terminal device fails to send a handover completion message to the conditional handover target cell successfully, it is considered that the terminal device fails to access the fourth conditional handover target cell.

In the embodiment of the present application, there are many reasons why the terminal device fails to be handed over to the fourth conditional handover target cell, which is not specifically limited in the embodiment of the present application.

Implementation mode 3: the second condition includes that the terminal equipment is successfully handed over to the handover target cell of the fifth condition.

The above-mentioned fifth conditional handover target cell belongs to at least one conditional handover target cell, or in other words, the fifth conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information stored in the terminal device.

The successful handover of the terminal device to the fifth conditional handover target cell can be understood as that the terminal device can communicate with other communication devices (eg, the network device to which the fifth conditional handover target cell belongs) through the fifth conditional handover target cell. In some implementation manners, before the handover timer expires, if the terminal device successfully completes the random access process with the fifth conditional handover target cell, it can be understood that the terminal device successfully accesses the fifth conditional handover target cell. In some other implementation manners, before the handover timer expires, if the terminal device successfully completes uplink synchronization with the fifth conditional handover target cell, it can be understood that the terminal device successfully accesses the fifth conditional handover target cell. In other implementation manners, before the handover timer times out, the terminal device successfully sends a reconfiguration complete message to the fifth conditional handover target cell, which can be understood as the terminal device successfully accessing the fifth conditional handover target cell. In some other implementation manners, if the terminal device successfully exchanges user data with the fifth conditional handover target cell, it may be understood that the terminal device successfully accesses the fifth conditional handover target cell. In some other implementation manners, if the terminal device successfully receives the first user data scheduling authorization instruction sent by the fifth conditional handover target cell, it may be understood that the terminal device successfully accesses the fifth conditional handover target cell. The foregoing scheduling grant instruction may include resource configuration for uplink data and/or resource configuration for downlink data, where the resource configuration may include time-frequency resource configuration.

In the embodiment of the present application, when the implementation mode 3 of the above second condition is satisfied, the terminal device does not start or stop the handover condition evaluation task related to the conditional switching, which is beneficial to improve the efficiency of the terminal device in performing the handover condition evaluation task related to the conditional handover, and prevents the terminal device from continuously performing the handover condition evaluation task related to the conditional handover just after performing the conditional handover once.

Implementation manner 4, the second condition includes that the adjacent cell measurement task of the terminal device is not enabled.

Based on the neighbor cell measurement task introduced in Implementation Mode 4 of the first condition, it can be seen that when the neighbor cell measurement task of the terminal device is enabled, it means that the current serving cell of the terminal device cannot provide better signal quality for the terminal device, or it can be considered that the terminal device may not be located in the center of the current serving cell at this time. On the contrary, when the adjacent cell measurement task of the terminal device is not enabled, it means that the current serving cell of the terminal device can provide better signal quality for the terminal device, or it can be considered that the terminal device may be located in the center of the current serving cell at this time. It is also not necessary for such end devices to perform conditional switching. Therefore, in order to improve the efficiency of the terminal device in performing handover condition evaluation tasks related to conditional handover (to avoid unnecessary handover condition evaluation related to conditional handover), in the embodiment of the present application, the adjacent cell measurement task of the terminal device may not be enabled as a condition for triggering the terminal device not to enable or stop the handover condition evaluation task related to conditional handover.

In this embodiment of the present application, based on the setting of the implementation mode 4 of the above second condition, it is possible to prevent the terminal device with better signal quality from performing the handover condition evaluation task related to the conditional handover, or in other words, to prevent the terminal device in the center of the current serving cell from performing the handover condition evaluation task related to the conditional handover, which is beneficial to improve the efficiency of the terminal device in performing the handover condition evaluation task related to the conditional handover.

In addition, in the embodiment of the present application, the terminal device’s adjacent cell measurement task is not enabled as the second condition to determine not to enable or stop the handover condition evaluation task related to the conditional handover, that is, the mechanism of the neighbor cell measurement task specified in the known communication protocol is reused as the condition for the terminal device not to enable or stop the handover condition evaluation task related to the conditional handover, which is beneficial to reduce the application of the method of the embodiment of the application.

Implementation manner 5, the second condition includes that the adjacent cell measurement task of the terminal device stops.

Based on the neighbor cell measurement task introduced in Implementation Mode 4 of the first condition, it can be seen that when the neighbor cell measurement task of the terminal device is enabled, it means that the current serving cell of the terminal device cannot provide better signal quality for the terminal device, or it can be considered that the terminal device may not be located in the center of the current serving cell at this time. On the contrary, when the adjacent cell measurement task of the terminal device stops, it means that the current serving cell of the terminal device can provide better signal quality for the terminal device, or it can be considered that the terminal device may return to the center of the current serving cell at this time. It is also not necessary for such end devices to perform conditional switching. Therefore, in order to improve the efficiency of the terminal device in performing the handover condition evaluation task related to the conditional handover, in the embodiment of the present application, the adjacent cell measurement task of the terminal device can be stopped as a condition for triggering the terminal device not to start or stop the handover condition evaluation task related to the conditional handover.

In the embodiment of the present application, based on the setting of the implementation mode 5 of the second condition above, it is possible to avoid allowing terminal devices with better signal quality to perform handover condition evaluation tasks related to conditional handover, or in other words, avoid allowing terminal devices in the center of the current serving cell to perform handover condition evaluation tasks related to conditional handover, which is conducive to improving the efficiency of terminal devices performing handover condition evaluation tasks related to conditional handover.

In addition, in the embodiment of the present application, the termination of the adjacent cell measurement task of the terminal device is used as the second condition to determine not to start or stop the handover condition evaluation task related to the conditional handover. That is to say, the mechanism of the adjacent cell measurement task specified in the known communication protocol is reused as the condition for the terminal device not to start or stop the handover condition evaluation task related to the conditional handover, which is beneficial to reduce the application of the method of the embodiment of the application.

Implementation manner 6, the second condition includes that the signal measurement result of the serving cell measured by the terminal device is greater than or equal to the second threshold.

The foregoing signal measurement result may indicate the service quality of the service provided by the current serving cell to the terminal device. In some implementation manners, the foregoing signal measurement results may include cell-level measurement results and/or beam-level measurement results, where the cell-level measurement results may be understood as measurement results with a granularity of a cell. Measurement results at the beam level can be understood as measurement results at the granularity of beams. In some other implementation manners, the measurement quantity corresponding to the above signal measurement result may be any one of RSRP, RSRQ or SINR.

It should be noted that the second threshold may be configured for the terminal device in a pre-configuration manner, a default configuration manner, a system broadcast message manner, or a dedicated signaling manner, which is not limited in this embodiment of the present application.

In this embodiment of the present application, based on the setting of implementation mode 6 of the above-mentioned second condition, it is possible to prevent the terminal device with better signal measurement results (for example, better signal quality) from starting the handover condition evaluation task related to the conditional handover, or to prevent the terminal device in the center of the current serving cell from starting the handover condition evaluation task related to the conditional handover, which is conducive to improving the efficiency of the terminal device in performing the handover condition evaluation task related to the conditional handover.

In addition, in the embodiment of the present application, the signal measurement result of the serving cell is greater than or equal to the second threshold as the second condition to determine whether to enable or stop the handover condition evaluation task related to the conditional handover, that is, an independent trigger condition is introduced for the condition that the terminal device does not enable or stop the handover condition evaluation task related to the conditional handover, which is beneficial to improve the independence of judging whether to enable or stop the handover condition evaluation task related to the conditional handover.

As mentioned above, in some cases, the conditional handover configuration stored by the terminal device corresponds to multiple conditional handover target cells. However, these multiple conditional handover target cells are not necessarily all neighbor cells of the current serving cell, and may be neighbor cells of the neighbor cell of the current serving cell, and the terminal device usually does not directly handover from the current serving cell to such conditional handover target cells. Therefore, in order to further reduce the power required by the terminal device to perform handover condition evaluation tasks related to conditional handover, for such conditional handover events associated with the conditional handover target cell (neighboring cell of an adjacent cell), the terminal device does not actually need to perform handover condition evaluation tasks related to conditional handover.

Therefore, in order to exclude the above conditional handover target cell, in the embodiment of the present application, the network device may send the first configuration information to the terminal device, indicating the range of conditional handover cells that need to perform handover condition evaluation tasks related to conditional handover. Correspondingly, the terminal device may determine, based on the first configuration information, a set of conditional handover target cells that need to perform handover condition evaluation. That is, the above method further includes: the network device sends the first configuration information to the terminal device; correspondingly, the terminal device determines, according to the conditional handover configuration information and the first configuration information, a set of conditional handover target cells that need to perform handover condition evaluation when a handover condition evaluation task related to conditional handover is started, wherein the set of conditional handover target cells includes the first conditional handover target cell.

In some implementation manners, the cells configured in the first configuration information may include neighboring cells of the current serving cell, and accordingly, the terminal device may use the cell configured in the first configuration information and the conditional handover cell corresponding to the conditional handover configuration information as the conditional handover target cell belonging to the above conditional handover target cell set. That is to say, the conditional handover target cells included in the set of conditional handover target cells can be understood as neighbor cells of the current serving cell of the terminal device.

In some implementation manners, the foregoing first configuration information includes one or more frequency point information of neighboring cells. In some other implementation manners, the first configuration information includes at least one physical cell identity (PCI) information associated with each frequency point information in the at least one frequency point information.

The above first configuration information is used to indicate the neighbors of the current serving cell of the terminal device, therefore, it can be understood that the first configuration information is associated with the current serving cell of the terminal device, or in other words, the first configuration information is associated with the configuration of the current serving cell of the terminal device. The first configuration information may be configured by the current serving cell of the terminal device. In some implementation manners, the first configuration information may be configured by the current serving cell for the terminal device through a system broadcast message or dedicated signaling. Of course, the above first configuration information may also be configured by the historical serving cell of the terminal device, which is not limited in this embodiment of the present application.

As described above, the terminal device may take the condition of belonging to the cell configured in the first configuration information and the conditional handover cell corresponding to the conditional handover configuration information as the conditional handover target cell belonging to the above conditional handover target cell set. That is to say, the second configuration information associated with the conditional handover target cells in the conditional handover target cell set matches the first configuration information, or in other words, the second configuration information associated with the conditional handover target cells in the conditional handover target cell set is partly or entirely the same as the first configuration information.

The content of the information contained in the first configuration information is introduced above, and accordingly, the second configuration information associated with the conditional handover target cell may include the frequency point information of the conditional handover target cell in the conditional handover target cell set. Of course, the second configuration information associated with the conditional handover target cell may also include the PCI of the conditional handover target cell in the conditional handover target cell set. At this time, the matching of the above-mentioned first configuration information with the second configuration information associated with the conditional handover target cell may be understood as the following situations.

In case 1, if the first configuration information includes the frequency point information of the neighboring cell, and the second configuration information associated with the conditional handover target cell includes the frequency point information of the conditional handover target cell, then the first configuration information and the second configuration information associated with the conditional handover target cell include that the frequency point information of the neighboring cell is the same as the frequency point information of the conditional handover target cell.

In case 2, if the first configuration information includes the frequency point information of the neighboring cell and the PCI associated with the frequency point of the neighboring cell, and the second configuration information associated with the conditional handover target cell includes the frequency point information of the conditional handover target cell, then the first configuration information and the second configuration information associated with the conditional handover target cell match include that the frequency point information of the neighboring cell in the first configuration information is the same as the frequency point information of the conditional handover target cell in the second configuration information associated with the conditional handover target cell.

In case 3, if the first configuration information includes the frequency point information of the neighboring cell and the PCI associated with the frequency point of the neighboring cell, and the second configuration information associated with the conditional handover target cell includes the frequency point information of the conditional handover target cell and the PCI associated with the frequency point of the conditional handover target cell, then the first configuration information and the second configuration information associated with the conditional handover target cell include the frequency point information of the neighboring cell in the first configuration information and the PCI associated with the frequency point of the adjacent cell, and the frequency point information of the conditional handover target cell and the frequency point association of the conditional handover target cell in the second configuration information associated with the conditional handover target cell PCI same.

The method of determining the set of conditional handover target cells is introduced above, so for the conditional handover target cells in the conditional handover configuration information that do not belong to the set of conditional handover target cells, the terminal device does not evaluate whether the conditional handover events associated with such conditional handover target cells are met. Wherein the following conditional handover configuration information does not belong to the conditional handover target cells in the conditional handover target cell set, it can be understood that the second configuration information of such conditional handover target cells does not match the first configuration information. The following takes the sixth conditional handover target cell corresponding to the conditional handover configuration information as an example, where the sixth conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information. Assuming that the conditional handover configuration information includes the second configuration information of the sixth conditional handover target cell, and part or all of the information in the second configuration information of the sixth conditional handover target cell does not match the first configuration information, then the terminal device does not evaluate whether the conditional handover event associated with the sixth conditional handover target cell is satisfied.

In some implementation manners, the second configuration information of the sixth conditional handover target cell includes frequency point information of the sixth conditional handover target cell. In some other implementation manners, the second configuration information of the sixth conditional handover target cell includes the PCI associated with the frequency point information of the sixth conditional handover target cell.

In the embodiment of the present application, the above-mentioned first configuration information may belong to the information in the frequency point configuration of the neighboring cell, or the first configuration information may be the frequency point configuration of the neighboring cell. At this time, the first configuration information may be configured through a system broadcast message of the current serving cell of the terminal device.

For example, the conditional handover configuration information stored in the terminal device corresponds to five conditional handover target cells, and the corresponding cell frequencies used by the five conditional handover target cells are f1, f2, f3, f4 and f5 respectively. The cell frequency corresponding to the current serving cell of the terminal device is f0, and the adjacent cell frequencies contained in the adjacent cell frequency information (ie, the first configuration information) of the current serving cell are f1, f2, and f3. That is, the conditional handover target cells corresponding to the frequency points f1, f2, and f3 form a set of conditional handover target cells.

At this time, if the terminal device starts the handover condition evaluation task related to the conditional handover when the first condition is met, it is unnecessary to evaluate the conditional handover events associated with the five conditional handover target cells. Because the above conditional handover target cells with frequencies f4 and f5 are not adjacent cells of the current serving cell, and the adjacent cells of the current serving cell may only have the conditional handover target cells corresponding to f1, f2, and f3, therefore, the terminal device can evaluate the conditional handover events associated with the conditional handover target cells corresponding to f1, f2, and f3 through the handover condition evaluation tasks related to conditional handover.

Assume that the above conditional handover configuration information corresponding to the five conditional handover target cells is valid, and the terminal device is handed over from the cell corresponding to the frequency point f0 to the cell corresponding to the frequency point f1, and the adjacent cell frequency points included in the frequency point information of the serving cell corresponding to the frequency point f1 are f2, f3, and f4. At this time, if the first condition is satisfied, the terminal device may start the handover condition evaluation task related to the conditional handover to evaluate the conditional handover events associated with the conditional handover target cells corresponding to the frequency points f2, f3, and f4.

For another example, the conditional handover configuration information stored in the terminal device corresponds to five conditional handover target cells, and the cell frequencies and PCIs corresponding to the five conditional handover target cells are {f1, PCI2}, {f2, PCI3}, {f3, PCI4}, {f4, PCI5} and {f5, PCI6} respectively. The cell frequency corresponding to the current serving cell of the terminal device is f0, and the frequency of the neighboring cell and the PCI of the neighboring cell contained in the frequency point information of the neighboring cell of the current serving cell (that is, the first configuration information above) are {f1, {PCI1, PCI2 and PCI3}}, {f2, {PCI1, PCI2 and PCI3}} and {f3, {PCI1, PCI2 and PCI3}} respectively. At this time, the frequency points and PCIs corresponding to the conditional handover target cells contained in the conditional handover target cell set are respectively {f1, PCI2} and {f2, PCI3}.

At this time, since the adjacent cell of the current serving cell does not include the cell corresponding to {f3, PCI4}, and the frequency points f4 and f5 are not adjacent cell frequency points of the current serving cell, then if the first condition is met, the terminal device can start the handover condition evaluation task related to the conditional handover to evaluate the conditional handover event associated with the conditional handover target cell in the conditional handover target cell set, and ignore the evaluation of the conditional handover event associated with the conditional handover target cell corresponding to the frequency points f3, f4, and f5.

In this embodiment of the present application, the foregoing first configuration information may also be configured through dedicated signaling. In this case, the first configuration information may also be referred to as "measurement restriction configuration".

For example, the conditional handover configuration information stored in the terminal device corresponds to five conditional handover target cells, and the corresponding cell frequencies used by the five conditional handover target cells are f1, f2, f3, f4 and f5 respectively. The cell frequency corresponding to the current serving cell of the terminal device is f1, and the frequency points of neighboring cells included in the measurement restriction configuration (ie, the first configuration information) of the current serving cell are f2, f3, and f4. That is, the conditional handover target cells corresponding to the frequency points f2, f3, and f4 form a set of conditional handover target cells.

At this time, if the terminal device starts the handover condition evaluation task related to the conditional handover to evaluate the conditional handover events associated with the five conditional handover target cells when the first condition is met, it is not necessary. Because the above-mentioned conditional handover target cell with frequency f5 is not a neighboring cell of the current serving cell, and the neighboring cells of the current serving cell may only have the conditional handover target cells corresponding to f2, f3, and f4, therefore, the terminal device can evaluate the conditional handover events associated with the conditional handover target cells corresponding to f2, f3, and f4 through the handover condition evaluation task related to the conditional handover.

For another example, the conditional handover configuration information stored in the terminal device corresponds to five conditional handover target cells, and the cell frequencies and PCIs corresponding to the five conditional handover target cells are {f1, PCI2}, {f2, PCI3}, {f3, PCI4}, {f4, PCI5} and {f5, PCI6} respectively. The cell frequency corresponding to the current serving cell of the terminal device is f1, and the frequency points of the neighboring cells and the PCIs of the neighboring cells included in the measurement restriction configuration of the current serving cell are {f2, {PCI1, PCI2 and PCI3}}, {f3, {PCI1, PCI2 and PCI3}} and {f4, {PCI1, PCI2 and PCI3}} respectively. At this time, the frequency points and PCIs corresponding to the conditional handover target cells included in the conditional handover target cell set are {f2, PCI3}.

At this time, since the adjacent cells of the current serving cell do not include the cells corresponding to {f1, PCI2}, {f3, PCI4}, and {f4, PCI5}, and the frequency point f5 is not the frequency point of the adjacent cell of the current serving cell, then in the case of meeting the first condition, the terminal device can start the handover condition evaluation task related to the conditional handover to evaluate the conditional handover events associated with the conditional handover target cells in the set of conditional handover target cells, and ignore the conditions associated with the conditional handover target cells corresponding to the frequency points f1, f3, f4, and f5 Evaluation of toggle events.

It should be noted that, if the current serving cell of the terminal device corresponds to a valid measurement restriction configuration, the terminal device may switch the target cell set based on the determination condition of the measurement restriction configuration. If the current serving cell of the terminal device does not have a corresponding effective measurement restriction configuration (for example: the target cell to which the terminal device is handed over (that is, the current serving cell of the terminal device) is not a conditional handover target cell), the terminal device can determine the set of conditional handover target cells based on the frequency point configuration of the neighboring cell of the serving cell.

Of course, in this embodiment of the present application, the above first configuration information may also indicate the conditional handover target cell among the one or more conditional handover cells corresponding to the conditional handover configuration information that does not need to be evaluated to satisfy the handover condition. The embodiment of the present application does not limit the specific content of the foregoing first configuration information.

As communication systems become more and more widely used, more and more types of terminal equipment are included, and each terminal equipment has different capabilities. Therefore, in the embodiment of the present application, the terminal device may be configured to report the capability of the terminal device to the network device before executing the method shown in FIG. 6 . Referring to FIG. 7, the above method further includes step S710. In step S710, the terminal device sends capability information to the network device. Wherein, the capability information is used to indicate one or more of the following terminal capabilities: whether the terminal device supports starting the handover condition evaluation task if the first condition is met; whether the terminal device supports not starting or stopping the handover condition evaluation task if the second condition is met; whether the terminal device supports determining the conditional handover target cell set according to the conditional handover configuration information and the first configuration information, and step S710 is an optional step.

In some cases, the above method shown in FIG. 6 can be used as an optional conditional switching mechanism. Correspondingly, the network device can determine whether the terminal device needs to execute the method shown in FIG. 6 . For example, for a terminal device with sufficient power or convenient charging, the network device may instruct such terminal device not to use the method shown in FIG. 6 . For terminal devices with insufficient power or inconvenient charging, the network device may instruct such terminal devices to adopt the method shown in FIG. 6 . Referring to FIG. 7, before the method shown in FIG. 6, the above method further includes step S720. In step S720, the network device sends first indication information to the terminal device, where step S720 is an optional step.

Wherein, the first indication information is used to indicate one or more of the following information: whether the terminal device is enabled to start the handover condition evaluation task if the first condition is met; whether the terminal device is enabled to not start or stop the handover condition evaluation task if the second condition is met; whether the terminal device is enabled to determine the conditional handover target cell set according to the conditional handover configuration information and the first configuration information.

It should be noted that, in the embodiment of the present application, the above-mentioned solution of the terminal device sending the capability information and the solution of the network device sending the indication information may be used alone or in combination. In the case where the scheme of sending capability information by terminal equipment and the scheme of sending indication information by network equipment are used in combination, this embodiment of the present application does not limit the sequence between the above sending capability information and sending indication information. In some implementation manners, the terminal device may send capability information first, and accordingly, the network device may send indication information to the terminal device based on the received capability information.

The method embodiment of the present application is described in detail above with reference to FIG. 1 to FIG. 7 , and the device embodiment of the present application is described in detail below in conjunction with FIG. 8 to FIG. 10 . It should be understood that the descriptions of the method embodiments correspond to the descriptions of the device embodiments, therefore, for parts not described in detail, reference may be made to the foregoing method embodiments.

FIG. 8 is a schematic diagram of a terminal device according to an embodiment of the present application. The terminal device shown in FIG. 8 includes: a processing unit 810 .

If the first condition is met, the processing unit 810 is configured to start a handover condition evaluation task related to conditional handover; and/or

If the second condition is met, the processing unit 810 is further configured not to start or stop the handover condition evaluation task related to the conditional handover,

Wherein, the handover condition evaluation task related to the conditional handover is used to evaluate whether the conditional handover event associated with the first conditional handover target cell is satisfied, the first conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information configured by the network device, and the conditional handover configuration information configured by the network device includes configuration information corresponding to the at least one conditional handover target cell.

In a possible implementation manner, the conditional handover configuration information configured by the network device is configured by a current serving cell of the terminal device or by a historical serving cell of the terminal device.

In a possible implementation manner, the first condition includes one or more of the following conditions: the terminal device successfully receives the first reconfiguration message sent by the network device; the terminal device fails to switch to a second conditional handover target cell, and the second conditional handover target cell belongs to the at least one conditional handover target cell; the terminal device successfully switches to a third conditional handover target cell, and the third conditional handover target cell belongs to the at least one conditional handover target cell;

In a possible implementation manner, the second condition includes one or more of the following conditions: the terminal device successfully receives the second reconfiguration message sent by the network device; the terminal device fails to switch to a fourth conditional handover target cell, and the fourth conditional handover target cell belongs to the at least one conditional handover target cell; the terminal device successfully switches to a fifth conditional handover target cell, and the fifth conditional handover target cell belongs to the at least one conditional handover target cell; The result is greater than or equal to the second threshold.

In a possible implementation manner, the first receiving unit is configured to receive the first configuration information sent by the network device; the processing unit is configured to determine, according to the conditional handover configuration information and the first configuration information, a set of conditional handover target cells that need to perform handover condition evaluation when the handover condition evaluation task related to the conditional handover is started, and the set of conditional handover target cells includes the first conditional handover target cell.

In a possible implementation manner, the first configuration information includes at least one frequency point information of a neighboring cell.

In a possible implementation manner, the first configuration information includes at least one physical cell identity (PCI) information associated with each frequency point information in the at least one frequency point information.

In a possible implementation manner, the first configuration information is associated with a current serving cell of the terminal device.

In a possible implementation manner, the first configuration information is configured in at least one of the following manners: a predefined manner, a default configuration manner, a system broadcast message manner, and a dedicated signaling manner.

In a possible implementation manner, the second configuration information associated with the conditional handover target cell in the conditional handover target cell set matches the first configuration information.

In a possible implementation manner, the conditional handover configuration information includes second configuration information of a sixth conditional handover target cell, and part or all of the information in the second configuration information of the sixth conditional handover target cell does not match the first configuration information, and the terminal device does not evaluate whether a conditional handover event associated with the sixth conditional handover target cell is satisfied.

In a possible implementation manner, the second configuration information of the sixth conditional handover target cell includes frequency point information of the sixth conditional handover target cell.

In a possible implementation manner, the second configuration information of the sixth conditional handover target cell includes a PCI associated with frequency point information of the sixth conditional handover target cell.

In a possible implementation manner, the second receiving unit is configured to receive first indication information sent by the network device, where the first indication information is used to indicate one or more of the following information: whether the terminal device is enabled to start a handover condition evaluation task related to the conditional handover if the first condition is met; whether the terminal device is enabled to not start or stop the handover condition evaluation task related to the conditional handover if the second condition is met; whether the terminal device is enabled to determine the conditional handover target cell set according to the conditional handover configuration information and the first configuration information.

In a possible implementation manner, the sending unit is configured to send capability information to the network device, where the capability information is used to indicate one or more of the following terminal capabilities: whether the terminal device supports starting the handover condition evaluation task related to the conditional handover if the first condition is met; whether the terminal device supports not starting or stopping the handover condition evaluation task if the second condition related to the conditional handover is met; whether the terminal device supports determining the conditional handover target cell set according to the conditional handover configuration information and the first configuration information.

In a possible implementation manner, the at least one conditional handover target cell includes a primary cell PCell or a primary secondary cell PSCell configured for the terminal device.

Fig. 8 is a schematic diagram of a network device according to an embodiment of the present application. The network device shown in FIG. 8 includes: a sending unit 810 .

The sending unit 810 is configured to send a reconfiguration message to the terminal device, the reconfiguration message is used to instruct the terminal device to start a handover condition evaluation task related to conditional handover, and/or, the reconfiguration message is used to instruct the terminal device not to start or stop the handover condition evaluation task related to the conditional handover, wherein the handover condition evaluation task related to conditional handover is used to evaluate whether a conditional handover event associated with a first conditional handover target cell is satisfied, wherein the first conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information configured by the network device, and the condition configured by the network device The handover configuration information includes configuration information corresponding to the at least one conditional handover target cell.

In a possible implementation manner, the conditional handover configuration information configured by the network device is configured by a current serving cell of the terminal device or by a historical serving cell of the terminal device.

In a possible implementation manner, the sending unit is further configured to: send first configuration information to the terminal device, the first configuration information is used to determine a set of conditional handover target cells, the set of conditional handover target cells includes conditional handover target cells associated with a conditional handover event that needs to perform handover condition evaluation when the handover condition evaluation task related to the conditional handover is started, and the set of conditional handover target cells includes the first conditional handover target cell.

In a possible implementation manner, the first configuration information includes at least one frequency point information of a neighboring cell.

In a possible implementation manner, the first configuration information includes at least one physical cell identity (PCI) information associated with each frequency point information in the at least one frequency point information.

In a possible implementation manner, the first configuration information is associated with a current serving cell of the terminal device.

In a possible implementation manner, the first configuration information is configured in at least one of the following manners: a predefined manner, a default manner, a system broadcast message manner, and a dedicated signaling manner.

In a possible implementation manner, the second configuration information associated with the conditional handover target cell in the conditional handover target cell set matches the first configuration information.

In a possible implementation manner, the conditional handover configuration information includes second configuration information of a sixth conditional handover target cell, and part or all of the information in the second configuration information of the sixth conditional handover target cell does not match the first configuration information, and the terminal device does not evaluate whether a conditional handover event associated with the sixth conditional handover target cell is satisfied.

In a possible implementation manner, the second configuration information of the sixth conditional handover target cell includes frequency point information of the sixth conditional handover target cell.

In a possible implementation manner, the second configuration information of the sixth conditional handover target cell includes a PCI associated with frequency point information of the sixth conditional handover target cell.

In a possible implementation manner, the sending unit is configured to send first indication information to the terminal device, where the first indication information is used to indicate one or more of the following information: whether the terminal device is enabled to start a handover condition evaluation task related to the conditional handover if a first condition is met; whether the terminal device is enabled to not start or stop a handover condition evaluation task related to the conditional handover if a second condition is met; whether the terminal device is enabled to determine the conditional handover target cell set according to the conditional handover configuration information and the first configuration information.

In a possible implementation manner, the receiving unit is configured to receive capability information sent by the terminal device, where the capability information is used to indicate one or more of the following terminal capabilities: whether the terminal device supports starting a handover condition evaluation task related to the conditional handover if the first condition is met; whether the terminal device supports not starting or stopping a handover condition evaluation task related to the conditional handover if the second condition is met; whether the terminal device supports determining the conditional handover target cell set according to the conditional handover configuration information and the first configuration information.

In a possible implementation manner, the first condition includes one or more of the following conditions: the terminal device successfully receives the reconfiguration message; the terminal device fails to switch to a second conditional handover target cell, and the second conditional handover target cell belongs to the at least one conditional handover target cell; the terminal device successfully switches to a third conditional handover target cell, and the third conditional handover target cell belongs to the at least one conditional handover target cell;

In a possible implementation manner, the second condition includes one or more of the following conditions: the terminal device successfully receives the reconfiguration message; the terminal device fails to switch to a fourth conditional handover target cell, and the fourth conditional handover target cell belongs to the at least one conditional handover target cell; the terminal device successfully switches to a fifth conditional handover target cell, and the fifth conditional handover target cell belongs to the at least one conditional handover target cell; threshold.

In a possible implementation manner, the at least one conditional handover target cell includes a primary cell PCell or a primary secondary cell PSCell configured for the terminal device.

Fig. 10 is a schematic structural diagram of a communication device according to an embodiment of the present application. The dashed line in Figure 10 indicates that the unit or module is optional. The apparatus 1000 may be used to implement the methods described in the foregoing method embodiments. The apparatus 1000 may be a chip, a terminal device or a network device.

Apparatus 1000 may include one or more processors 1010 . The processor 1010 can support the device 1000 to implement the methods described in the foregoing method embodiments. The processor 1010 may be a general purpose processor or a special purpose processor. For example, the processor may be a central processing unit (central processing unit, CPU). Alternatively, the processor may also be other general-purpose processors, digital signal processors (digital signal processors, DSPs), application specific integrated circuits (application specific integrated circuits, ASICs), off-the-shelf programmable gate arrays (field programmable gate arrays, FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like.

Apparatus 1000 may also include one or more memories 1020 . A program is stored in the memory 1020, and the program can be executed by the processor 1010, so that the processor 1010 executes the methods described in the foregoing method embodiments. The memory 1020 may be independent of the processor 1010 or may be integrated in the processor 1010 .

The apparatus 1000 may also include a transceiver 1030 . The processor 1010 can communicate with other devices or chips through the transceiver 1030 . For example, the processor 1010 may send and receive data with other devices or chips through the transceiver 1030 .

The embodiment of the present application also provides a computer-readable storage medium for storing programs. The computer-readable storage medium can be applied to the terminal or the network device provided in the embodiments of the present application, and the program enables the computer to execute the methods performed by the terminal or the network device in the various embodiments of the present application.

The embodiment of the present application also provides a computer program product. The computer program product includes programs. The computer program product can be applied to the terminal or the network device provided in the embodiments of the present application, and the program enables the computer to execute the methods performed by the terminal or the network device in the various embodiments of the present application.

The embodiment of the present application also provides a computer program. The computer program can be applied to the terminal or the network device provided in the embodiments of the present application, and the computer program enables the computer to execute the methods performed by the terminal or the network device in the various embodiments of the present application.

It should be understood that the above-mentioned serving cell (or current serving cell) has slightly different meanings in different scenarios. In a CHO scenario or a conditional PCell replacement scenario, the above serving cell may be the PCell that the terminal device is currently connected to, for example, may include the PCell that the terminal device is connected to after the terminal device performs a conditional handover. For another example, it may also include the PCell connected to the terminal device before the terminal device executes the conditional handover.

In a CPA scenario or a conditional PSCell cell addition scenario, the above serving cell may be the PSCell that the terminal device is currently connected to, for example, may include the PSCell that the terminal device is connected to after the terminal device performs a conditional handover. For another example, it may also include the PSCell connected to the terminal device before the terminal device executes the conditional handover.

In a CPC scenario or a conditional PSCell cell change scenario, the above-mentioned serving cell may be the PSCell to which the terminal device is currently connected, for example, may include the PSCell to which the terminal device is connected after performing a conditional handover. For another example, it may also include the PSCell connected to the terminal device before the terminal device executes the conditional handover.

In the CHO and CPA combined configuration scenario or in the CHO and CPC combined configuration scenario, the serving cell may include the PCell and the PSCell to which the terminal device is currently connected. For example, it may include the PCell and the PSCell to which the terminal device is connected after the terminal device performs a conditional handover. For another example, it may also include the PCell and the PSCell connected to the terminal device before the terminal device executes the conditional handover.

It should also be understood that the terms "system" and "network" may be used interchangeably in this application. In addition, the terms used in the application are only used to explain the specific embodiments of the application, and are not intended to limit the application. The terms "first", "second", "third" and "fourth" in the specification and claims of the present application and the drawings are used to distinguish different objects, rather than to describe a specific order. Furthermore, the terms "include" and "have", as well as any variations thereof, are intended to cover a non-exclusive inclusion.

In the embodiments of the present application, the "indication" mentioned may be a direct indication, may also be an indirect indication, and may also mean that there is an association relationship. For example, A indicates B, which may mean that A directly indicates B, for example, B can be obtained through A; it may also indicate that A indirectly indicates B, for example, A indicates C, and B can be obtained through C; it may also indicate that there is an association relationship between A and B.

In this embodiment of the application, "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B may also be determined according to A and/or other information.

In this embodiment of the application, the term "corresponding" may mean that there is a direct or indirect corresponding relationship between the two, or that there is an associated relationship between the two, or that there is a relationship between indicating and being instructed, configuring and being configured, etc.

In the embodiment of this application, "predefinition" or "preconfiguration" can be realized by pre-saving corresponding codes, tables or other methods that can be used to indicate relevant information in devices (for example, including terminal devices and network devices), and this application does not limit its specific implementation. For example, pre-defined may refer to defined in the protocol.

In the embodiment of the present application, the "protocol" may refer to a standard protocol in the communication field, for example, may include the LTE protocol, the NR protocol, and related protocols applied to future communication systems, which is not limited in the present application.

The term "and/or" in the embodiment of the present application is only a relationship describing the relationship between related objects, which means that there may be three relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

In various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the order of execution, and the execution order of each process should be determined by its functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not implemented. In another point, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to realize the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, each unit may exist separately physically, or two or more units may be integrated into one unit.

In the above embodiments, all or part of them may be implemented by software, hardware, firmware or any combination thereof. When implemented using software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the processes or functions according to the embodiments of the present application will be generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that can be read by a computer, or a data storage device including a server, a data center, and the like integrated with one or more available media. The available medium may be a magnetic medium (for example, a floppy disk, a hard disk, or a magnetic tape), an optical medium (for example, a digital versatile disc (digital video disc, DVD)), or a semiconductor medium (for example, a solid state disk (solid state disk, SSD)), etc.

The above is only a specific embodiment of the application, but the scope of protection of the application is not limited thereto. Anyone skilled in the art within the scope of the technology disclosed in this application can easily think of changes or replacements, which should be covered within the scope of protection of the application. Therefore, the protection scope of the present application should be determined by the protection scope of the claims.

Claims (76)

A communication method, characterized in that, comprising: If the first condition is met, the terminal device starts a handover condition evaluation task related to conditional handover; and/or If the second condition is met, the terminal device does not start or stop the handover condition evaluation task related to the conditional handover, Wherein, the handover condition evaluation task related to the conditional handover is used to evaluate whether the conditional handover event associated with the first conditional handover target cell is satisfied, the first conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information configured by the network device, and the conditional handover configuration information configured by the network device includes configuration information corresponding to the at least one conditional handover target cell. The method according to claim 1, wherein the conditional handover configuration information configured by the network device is configured by a current serving cell of the terminal device or by a historical serving cell of the terminal device. The method according to claim 1 or 2, wherein the first condition comprises one or more of the following conditions: The terminal device successfully receives the first reconfiguration message sent by the network device; The terminal device is unsuccessfully handed over to a second conditional handover target cell, and the second conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a third conditional handover target cell, and the third conditional handover target cell belongs to the at least one conditional handover target cell; The adjacent cell measurement task of the terminal device is started; The signal measurement result of the serving cell measured by the terminal device is less than or equal to the first threshold. The method according to any one of claims 1-3, wherein the second condition comprises one or more of the following conditions: The terminal device successfully receives the second reconfiguration message sent by the network device; The terminal device is unsuccessfully handed over to a fourth conditional handover target cell, and the fourth conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a fifth conditional handover target cell, and the fifth conditional handover target cell belongs to the at least one conditional handover target cell; The neighbor cell measurement task of the terminal device is not enabled; The neighbor cell measurement task of the terminal device is stopped; The signal measurement result of the serving cell measured by the terminal device is greater than or equal to the second threshold. The method according to any one of claims 1-4, further comprising: The terminal device receives the first configuration information sent by the network device; The terminal device determines, according to the conditional handover configuration information and the first configuration information, a set of conditional handover target cells that need to perform handover condition evaluation when the handover condition evaluation task related to the conditional handover is started, and the set of conditional handover target cells includes the first conditional handover target cell. The method according to claim 5, wherein the first configuration information includes at least one frequency point information of a neighboring cell. The method according to claim 6, wherein the first configuration information includes at least one physical cell identity (PCI) information associated with each frequency point information in the at least one frequency point information. The method according to any one of claims 5-7, wherein the first configuration information is associated with a current serving cell of the terminal device. The method according to any one of claims 5-8, wherein the first configuration information is configured in at least one of the following ways: a predefined way, a default configuration way, a system broadcast message way, and a dedicated signaling way. The method according to any one of claims 5-9, wherein the second configuration information associated with the conditional handover target cells in the conditional handover target cell set matches the first configuration information. The method according to any one of claims 5-10, wherein the conditional handover configuration information includes second configuration information of a sixth conditional handover target cell, and part or all of the information in the second configuration information of the sixth conditional handover target cell does not match the first configuration information, and the terminal device does not evaluate whether a conditional handover event associated with the sixth conditional handover target cell is satisfied. The method according to claim 11, wherein the second configuration information of the sixth conditional handover target cell includes frequency point information of the sixth conditional handover target cell. The method according to claim 11 or 12, wherein the second configuration information of the sixth conditional handover target cell includes PCI associated with the frequency point information of the sixth conditional handover target cell. The method according to any one of claims 5-13, further comprising: The terminal device receives first indication information sent by the network device, where the first indication information is used to indicate one or more of the following information: Whether the terminal device is enabled to start a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device is enabled to not start or stop the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device is enabled to determine the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The method according to any one of claims 5-14, further comprising: The terminal device sends capability information to the network device, where the capability information is used to indicate one or more of the following terminal capabilities: Whether the terminal device supports starting a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device supports not starting or stopping the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device supports determining the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The method according to any one of claims 1-15, wherein the at least one conditional handover target cell includes a primary cell PCell or a primary secondary cell PSCell configured for the terminal device. A communication method, characterized in that, comprising: The network device sends a reconfiguration message to the terminal device, where the reconfiguration message is used to instruct the terminal device to enable handover condition evaluation tasks related to conditional handover, and/or The reconfiguration message is used to instruct the terminal device not to start or stop the handover condition evaluation task related to the conditional handover, Wherein, the handover condition evaluation task related to the conditional handover is used to evaluate whether the conditional handover event associated with the first conditional handover target cell is satisfied, the first conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information configured by the network device, and the conditional handover configuration information configured by the network device includes configuration information corresponding to the at least one conditional handover target cell. The method according to claim 17, wherein the conditional handover configuration information configured by the network device is configured by the current serving cell of the terminal device or by the historical serving cell of the terminal device. The method according to claim 17 or 18, further comprising: The network device sends first configuration information to the terminal device, where the first configuration information is used to determine a set of conditional handover target cells, the set of conditional handover target cells includes conditional handover target cells associated with a conditional handover event that needs to perform handover condition evaluation when the handover condition evaluation task related to the conditional handover is started, and the set of conditional handover target cells includes the first conditional handover target cell. The method according to claim 19, wherein the first configuration information includes at least one frequency point information of a neighboring cell. The method according to claim 20, wherein the first configuration information includes at least one physical cell identity (PCI) information associated with each frequency point information in the at least one frequency point information. The method according to any one of claims 19-21, wherein the first configuration information is associated with the current serving cell of the terminal device. The method according to any one of claims 19-22, wherein the first configuration information is configured in at least one of the following ways: a predefined way, a default configuration way, a system broadcast message way, and a dedicated signaling way. The method according to any one of claims 19-23, wherein the second configuration information associated with the conditional handover target cells in the set of conditional handover target cells matches the first configuration information. The method according to any one of claims 19-24, wherein the conditional handover configuration information includes second configuration information of a sixth conditional handover target cell, and part or all of the information in the second configuration information of the sixth conditional handover target cell does not match the first configuration information, and the terminal device does not evaluate whether a conditional handover event associated with the sixth conditional handover target cell is satisfied. The method according to claim 25, wherein the second configuration information of the sixth conditional handover target cell includes frequency point information of the sixth conditional handover target cell. The method according to claim 26, wherein the second configuration information of the sixth conditional handover target cell includes PCI associated with the frequency point information of the sixth conditional handover target cell. The method according to any one of claims 19-27, further comprising: The network device sends first indication information to the terminal device, where the first indication information is used to indicate one or more of the following information: Whether the terminal device is enabled to start a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device is enabled to not start or stop the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device is enabled to determine the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The method of claim 28, further comprising: The network device receives capability information sent by the terminal device, where the capability information is used to indicate one or more of the following terminal capabilities: Whether the terminal device supports starting a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device supports not starting or stopping the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device supports determining the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The method according to claim 28 or 29, wherein the first condition comprises one or more of the following conditions: The terminal device successfully receives the reconfiguration message; The terminal device is unsuccessfully handed over to a second conditional handover target cell, and the second conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a third conditional handover target cell, and the third conditional handover target cell belongs to the at least one conditional handover target cell; The adjacent cell measurement task of the terminal device is started; The signal measurement result of the serving cell measured by the terminal device is less than or equal to the first threshold. The method according to any one of claims 28-30, wherein the second condition comprises one or more of the following conditions: The terminal device successfully receives the reconfiguration message; The terminal device is unsuccessfully handed over to a fourth conditional handover target cell, and the fourth conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a fifth conditional handover target cell, and the fifth conditional handover target cell belongs to the at least one conditional handover target cell; The neighbor cell measurement task of the terminal device is not enabled; The neighbor cell measurement task of the terminal device is stopped; The signal measurement result of the serving cell measured by the terminal device is greater than or equal to the second threshold. The method according to any one of claims 17-31, wherein the at least one conditional handover target cell includes a primary cell PCell or a primary secondary cell PSCell configured for the terminal device. A terminal device, characterized in that it includes: If the first condition is met, the processing unit is configured to start a handover condition evaluation task related to conditional handover; and/or If the second condition is met, the processing unit is configured not to start or stop the handover condition evaluation task related to the conditional handover, Wherein, the handover condition evaluation task related to the conditional handover is used to evaluate whether the conditional handover event associated with the first conditional handover target cell is satisfied, the first conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information configured by the network device, and the conditional handover configuration information configured by the network device includes configuration information corresponding to the at least one conditional handover target cell. The terminal device according to claim 33, wherein the conditional handover configuration information configured by the network device is configured by a current serving cell of the terminal device or by a historical serving cell of the terminal device. The terminal device according to claim 33 or 34, wherein the first condition includes one or more of the following conditions: The terminal device successfully receives the first reconfiguration message sent by the network device; The terminal device is unsuccessfully handed over to a second conditional handover target cell, and the second conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a third conditional handover target cell, and the third conditional handover target cell belongs to the at least one conditional handover target cell; The adjacent cell measurement task of the terminal device is started; The signal measurement result of the serving cell measured by the terminal device is less than or equal to the first threshold. The terminal device according to any one of claims 33-35, wherein the second condition includes one or more of the following conditions: The terminal device successfully receives the second reconfiguration message sent by the network device; The terminal device is unsuccessfully handed over to a fourth conditional handover target cell, and the fourth conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a fifth conditional handover target cell, and the fifth conditional handover target cell belongs to the at least one conditional handover target cell; The neighbor cell measurement task of the terminal device is not enabled; The neighbor cell measurement task of the terminal device is stopped; The signal measurement result of the serving cell measured by the terminal device is greater than or equal to the second threshold. The terminal device according to any one of claims 33-36, characterized in that, a first receiving unit, configured to receive first configuration information sent by the network device; The processing unit is configured to determine, according to the conditional handover configuration information and the first configuration information, a set of conditional handover target cells that need to perform handover condition evaluation when the handover condition evaluation task related to the conditional handover is started, and the set of conditional handover target cells includes the first conditional handover target cell. The terminal device according to claim 37, wherein the first configuration information includes at least one frequency point information of a neighboring cell. The terminal device according to claim 38, wherein the first configuration information includes at least one physical cell identity (PCI) information associated with each frequency point information in the at least one frequency point information. The terminal device according to any one of claims 37-39, wherein the first configuration information is associated with a current serving cell of the terminal device. The terminal device according to any one of claims 37-40, wherein the first configuration information is configured in at least one of the following ways: a predefined way, a default configuration way, a system broadcast message way, and a dedicated signaling way. The terminal device according to any one of claims 37-41, wherein the second configuration information associated with the conditional handover target cell in the conditional handover target cell set matches the first configuration information. The terminal device according to any one of claims 37-42, wherein the conditional handover configuration information includes second configuration information of a sixth conditional handover target cell, and part or all of the information in the second configuration information of the sixth conditional handover target cell does not match the first configuration information, and the terminal device does not evaluate whether a conditional handover event associated with the sixth conditional handover target cell is satisfied. The terminal device according to claim 43, wherein the second configuration information of the sixth conditional handover target cell includes frequency point information of the sixth conditional handover target cell. The terminal device according to claim 43 or 44, wherein the second configuration information of the sixth conditional handover target cell includes PCI associated with the frequency point information of the sixth conditional handover target cell. The terminal device according to any one of claims 37-45, characterized in that, The second receiving unit is configured to receive first indication information sent by the network device, where the first indication information is used to indicate one or more of the following information: Whether the terminal device is enabled to start a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device is enabled to not start or stop the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device is enabled to determine the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The terminal device according to any one of claims 37-46, characterized in that, A sending unit, configured to send capability information to the network device, where the capability information is used to indicate one or more of the following terminal capabilities: Whether the terminal device supports starting a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device supports not starting or stopping the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device supports determining the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The terminal device according to any one of claims 33-47, wherein the at least one conditional handover target cell includes a primary cell PCell or a primary secondary cell PSCell configured for the terminal device. A network device, characterized in that it includes: A sending unit, configured to send a reconfiguration message to the terminal device, where the reconfiguration message is used to instruct the terminal device to start a handover condition evaluation task related to conditional handover, and/or The reconfiguration message is used to instruct the terminal device not to start or stop the handover condition evaluation task related to the conditional handover, Wherein, the handover condition evaluation task related to the conditional handover is used to evaluate whether the conditional handover event associated with the first conditional handover target cell is satisfied, the first conditional handover target cell is one of at least one conditional handover target cell corresponding to the conditional handover configuration information configured by the network device, and the conditional handover configuration information configured by the network device includes configuration information corresponding to the at least one conditional handover target cell. The network device according to claim 49, wherein the conditional handover configuration information configured by the network device is configured by the current serving cell of the terminal device or by the historical serving cell of the terminal device. The network device according to claim 49 or 50, wherein the sending unit is further configured to: Sending first configuration information to the terminal device, where the first configuration information is used to determine a set of conditional handover target cells, the set of conditional handover target cells includes the conditional handover target cells associated with a conditional handover event that needs to perform handover condition evaluation when the handover condition evaluation task related to the conditional handover is started, and the set of conditional handover target cells includes the first conditional handover target cell. The network device according to claim 51, wherein the first configuration information includes at least one frequency point information of a neighboring cell. The network device according to claim 52, wherein the first configuration information includes at least one physical cell identity (PCI) information associated with each frequency point information in the at least one frequency point information. The network device according to any one of claims 51-53, wherein the first configuration information is associated with the current serving cell of the terminal device. The network device according to any one of claims 51-54, wherein the first configuration information is configured in at least one of the following ways: a predefined way, a default configuration way, a system broadcast message way, and a dedicated signaling way. The network device according to any one of claims 51-55, wherein the second configuration information associated with the conditional handover target cell in the conditional handover target cell set matches the first configuration information. The network device according to any one of claims 51-56, wherein the conditional handover configuration information includes second configuration information of a sixth conditional handover target cell, and part or all of the information in the second configuration information of the sixth conditional handover target cell does not match the first configuration information, and the terminal device does not evaluate whether a conditional handover event associated with the sixth conditional handover target cell is satisfied. The network device according to claim 57, wherein the second configuration information of the sixth conditional handover target cell includes frequency point information of the sixth conditional handover target cell. The network device according to claim 57 or 58, wherein the second configuration information of the sixth conditional handover target cell includes PCI associated with the frequency point information of the sixth conditional handover target cell. The network device according to any one of claims 51-59, wherein the sending unit is configured to: First indication information sent to the terminal device, where the first indication information is used to indicate one or more of the following information: Whether the terminal device is enabled to start a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device is enabled to not start or stop the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device is enabled to determine the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The network device of claim 60, wherein, A receiving unit, configured to receive capability information sent by the terminal device, where the capability information is used to indicate one or more of the following terminal capabilities: Whether the terminal device supports starting a handover condition evaluation task related to the conditional handover if the first condition is met; Whether the terminal device supports not starting or stopping the handover condition evaluation task related to the conditional handover if the second condition is met; Whether the terminal device supports determining the conditional handover target cell set according to the conditional handover configuration information and the first configuration information. The network device according to claim 60 or 61, wherein the first condition includes one or more of the following conditions: The terminal device successfully receives the reconfiguration message; The terminal device is unsuccessfully handed over to a second conditional handover target cell, and the second conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a third conditional handover target cell, and the third conditional handover target cell belongs to the at least one conditional handover target cell; The adjacent cell measurement task of the terminal device is started; The signal measurement result of the serving cell measured by the terminal device is less than or equal to the first threshold. The network device according to any one of claims 60-62, wherein the second condition includes one or more of the following conditions: The terminal device successfully receives the reconfiguration message; The terminal device is unsuccessfully handed over to a fourth conditional handover target cell, and the fourth conditional handover target cell belongs to the at least one conditional handover target cell; The terminal device is successfully handed over to a fifth conditional handover target cell, and the fifth conditional handover target cell belongs to the at least one conditional handover target cell; The neighbor cell measurement task of the terminal device is not enabled; The neighbor cell measurement task of the terminal device is stopped; The signal measurement result of the serving cell measured by the terminal device is greater than or equal to the second threshold. The network device according to any one of claims 49-63, wherein the at least one conditional handover target cell includes a primary cell PCell or a primary secondary cell PSCell configured for the terminal device. A terminal device, characterized by comprising a memory and a processor, the memory is used to store a program, and the processor is used to call the program in the memory to execute the method according to any one of claims 1-17. A network device, characterized by comprising a transceiver, a memory and a processor, the memory is used to store a program, and the processor is used to call the program in the memory, so as to execute the method according to any one of claims 18-32 through the transceiver. An apparatus, characterized by comprising a processor, configured to call a program from a memory to execute the method according to any one of claims 1-17. An apparatus, characterized by comprising a processor, configured to call a program from a memory to execute the method according to any one of claims 18-32. A chip, characterized by comprising a processor, configured to call a program from a memory, so that a device installed with the chip executes the method according to any one of claims 1-17. A chip, characterized by comprising a processor, configured to call a program from a memory, so that a device installed with the chip executes the method according to any one of claims 18-32. A computer-readable storage medium, characterized in that a program is stored thereon, and the program causes a computer to execute the method according to any one of claims 1-17. A computer-readable storage medium, characterized in that a program is stored thereon, and the program causes a computer to execute the method according to any one of claims 18-32. A computer program product, characterized by comprising a program, the program causes a computer to execute the method according to any one of claims 1-17. A computer program product, characterized by comprising a program, the program causes a computer to execute the method according to any one of claims 18-32. A computer program, characterized in that the computer program causes a computer to execute the method according to any one of claims 1-17. A computer program, characterized in that the computer program causes a computer to execute the method according to any one of claims 18-32.

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